linux_dsm_epyc7002/drivers/s390/scsi/zfcp_def.h
Benjamin Block 7e418833e6 scsi: zfcp: diagnostics buffer caching and use for exchange port data
The FCP channel exposes two central interfaces to receive information about
the local FCP-Adapter/-Port: Exchange Port and Exchange Config Data. Using
these commands can negatively impact the adapter if we allow them to be
sent at a very high rate.

The later parts of this patchset will introduce new user-interfaces to
receive more diagnostics from the adapter. To prevent any negative impact
from using those, this patch adds a simple caching-mechanism that will
prevent a malicious/faulty userspace-application from generating an
abnormal high amount of Exchange Port/Config Data traffic.

Relevant diagnostic data that is received via Exchange Config/Port Data is
cached in buffers associated with the corresponding adapter-struct.  Each
buffer is associated with a timestamp that signals how old the data is,
and, added via a following patch in this series, lets userspace-interfaces
determine when the data is too old and needs to be updated.

Buffer-updates are made during the normal response path of the
corresponding command. With this patch only the output of the Exchange Port
Data command is captured.

Link: https://lore.kernel.org/r/054ca020ce0a53dc0d9176428bea373898944e6a.1572018130.git.bblock@linux.ibm.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-10-28 22:16:14 -04:00

350 lines
11 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* zfcp device driver
*
* Global definitions for the zfcp device driver.
*
* Copyright IBM Corp. 2002, 2018
*/
#ifndef ZFCP_DEF_H
#define ZFCP_DEF_H
/*************************** INCLUDES *****************************************/
#include <linux/init.h>
#include <linux/moduleparam.h>
#include <linux/major.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/slab.h>
#include <linux/mempool.h>
#include <linux/syscalls.h>
#include <linux/scatterlist.h>
#include <linux/ioctl.h>
#include <scsi/fc/fc_fs.h>
#include <scsi/fc/fc_gs.h>
#include <scsi/scsi.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_fc.h>
#include <scsi/scsi_bsg_fc.h>
#include <asm/ccwdev.h>
#include <asm/debug.h>
#include <asm/ebcdic.h>
#include <asm/sysinfo.h>
#include "zfcp_fsf.h"
#include "zfcp_fc.h"
#include "zfcp_qdio.h"
/********************* FSF SPECIFIC DEFINES *********************************/
/* ATTENTION: value must not be used by hardware */
#define FSF_QTCB_UNSOLICITED_STATUS 0x6305
/*************** ADAPTER/PORT/UNIT AND FSF_REQ STATUS FLAGS ******************/
/*
* Note, the leftmost 12 status bits (3 nibbles) are common among adapter, port
* and unit. This is a mask for bitwise 'and' with status values.
*/
#define ZFCP_COMMON_FLAGS 0xfff00000
/* common status bits */
#define ZFCP_STATUS_COMMON_RUNNING 0x40000000
#define ZFCP_STATUS_COMMON_ERP_FAILED 0x20000000
#define ZFCP_STATUS_COMMON_UNBLOCKED 0x10000000
#define ZFCP_STATUS_COMMON_OPEN 0x04000000
#define ZFCP_STATUS_COMMON_ERP_INUSE 0x01000000
#define ZFCP_STATUS_COMMON_ACCESS_DENIED 0x00800000
#define ZFCP_STATUS_COMMON_ACCESS_BOXED 0x00400000
#define ZFCP_STATUS_COMMON_NOESC 0x00200000
/* adapter status */
#define ZFCP_STATUS_ADAPTER_MB_ACT 0x00000001
#define ZFCP_STATUS_ADAPTER_QDIOUP 0x00000002
#define ZFCP_STATUS_ADAPTER_SIOSL_ISSUED 0x00000004
#define ZFCP_STATUS_ADAPTER_XCONFIG_OK 0x00000008
#define ZFCP_STATUS_ADAPTER_HOST_CON_INIT 0x00000010
#define ZFCP_STATUS_ADAPTER_SUSPENDED 0x00000040
#define ZFCP_STATUS_ADAPTER_ERP_PENDING 0x00000100
#define ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED 0x00000200
#define ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED 0x00000400
/* remote port status */
#define ZFCP_STATUS_PORT_PHYS_OPEN 0x00000001
#define ZFCP_STATUS_PORT_LINK_TEST 0x00000002
/* FSF request status (this does not have a common part) */
#define ZFCP_STATUS_FSFREQ_ERROR 0x00000008
#define ZFCP_STATUS_FSFREQ_CLEANUP 0x00000010
#define ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED 0x00000040
#define ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED 0x00000080
#define ZFCP_STATUS_FSFREQ_TMFUNCFAILED 0x00000200
#define ZFCP_STATUS_FSFREQ_DISMISSED 0x00001000
#define ZFCP_STATUS_FSFREQ_XDATAINCOMPLETE 0x00020000
/************************* STRUCTURE DEFINITIONS *****************************/
/**
* enum zfcp_erp_act_type - Type of ERP action object.
* @ZFCP_ERP_ACTION_REOPEN_LUN: LUN recovery.
* @ZFCP_ERP_ACTION_REOPEN_PORT: Port recovery.
* @ZFCP_ERP_ACTION_REOPEN_PORT_FORCED: Forced port recovery.
* @ZFCP_ERP_ACTION_REOPEN_ADAPTER: Adapter recovery.
*
* Values must fit into u8 because of code dependencies:
* zfcp_dbf_rec_trig(), &zfcp_dbf_rec_trigger.want, &zfcp_dbf_rec_trigger.need;
* zfcp_dbf_rec_run_lvl(), zfcp_dbf_rec_run(), &zfcp_dbf_rec_running.rec_action.
*/
enum zfcp_erp_act_type {
ZFCP_ERP_ACTION_REOPEN_LUN = 1,
ZFCP_ERP_ACTION_REOPEN_PORT = 2,
ZFCP_ERP_ACTION_REOPEN_PORT_FORCED = 3,
ZFCP_ERP_ACTION_REOPEN_ADAPTER = 4,
};
/*
* Values must fit into u16 because of code dependencies:
* zfcp_dbf_rec_run_lvl(), zfcp_dbf_rec_run(), zfcp_dbf_rec_run_wka(),
* &zfcp_dbf_rec_running.rec_step.
*/
enum zfcp_erp_steps {
ZFCP_ERP_STEP_UNINITIALIZED = 0x0000,
ZFCP_ERP_STEP_PHYS_PORT_CLOSING = 0x0010,
ZFCP_ERP_STEP_PORT_CLOSING = 0x0100,
ZFCP_ERP_STEP_PORT_OPENING = 0x0800,
ZFCP_ERP_STEP_LUN_CLOSING = 0x1000,
ZFCP_ERP_STEP_LUN_OPENING = 0x2000,
};
struct zfcp_erp_action {
struct list_head list;
enum zfcp_erp_act_type type; /* requested action code */
struct zfcp_adapter *adapter; /* device which should be recovered */
struct zfcp_port *port;
struct scsi_device *sdev;
u32 status; /* recovery status */
enum zfcp_erp_steps step; /* active step of this erp action */
unsigned long fsf_req_id;
struct timer_list timer;
};
/* holds various memory pools of an adapter */
struct zfcp_adapter_mempool {
mempool_t *erp_req;
mempool_t *gid_pn_req;
mempool_t *scsi_req;
mempool_t *scsi_abort;
mempool_t *status_read_req;
mempool_t *sr_data;
mempool_t *gid_pn;
mempool_t *qtcb_pool;
};
struct zfcp_adapter {
struct kref ref;
u64 peer_wwnn; /* P2P peer WWNN */
u64 peer_wwpn; /* P2P peer WWPN */
u32 peer_d_id; /* P2P peer D_ID */
struct ccw_device *ccw_device; /* S/390 ccw device */
struct zfcp_qdio *qdio;
u32 hydra_version; /* Hydra version */
u32 fsf_lic_version;
u32 adapter_features; /* FCP channel features */
u32 connection_features; /* host connection features */
u32 hardware_version; /* of FCP channel */
u16 timer_ticks; /* time int for a tick */
struct Scsi_Host *scsi_host; /* Pointer to mid-layer */
struct list_head port_list; /* remote port list */
rwlock_t port_list_lock; /* port list lock */
unsigned long req_no; /* unique FSF req number */
struct zfcp_reqlist *req_list;
u32 fsf_req_seq_no; /* FSF cmnd seq number */
rwlock_t abort_lock; /* Protects against SCSI
stack abort/command
completion races */
atomic_t stat_miss; /* # missing status reads*/
unsigned int stat_read_buf_num;
struct work_struct stat_work;
atomic_t status; /* status of this adapter */
struct list_head erp_ready_head; /* error recovery for this
adapter/devices */
wait_queue_head_t erp_ready_wq;
struct list_head erp_running_head;
rwlock_t erp_lock;
wait_queue_head_t erp_done_wqh;
struct zfcp_erp_action erp_action; /* pending error recovery */
atomic_t erp_counter;
u32 erp_total_count; /* total nr of enqueued erp
actions */
u32 erp_low_mem_count; /* nr of erp actions waiting
for memory */
struct task_struct *erp_thread;
struct zfcp_fc_wka_ports *gs; /* generic services */
struct zfcp_dbf *dbf; /* debug traces */
struct zfcp_adapter_mempool pool; /* Adapter memory pools */
struct fc_host_statistics *fc_stats;
struct fsf_qtcb_bottom_port *stats_reset_data;
unsigned long stats_reset;
struct delayed_work scan_work;
struct work_struct ns_up_work;
struct service_level service_level;
struct workqueue_struct *work_queue;
struct device_dma_parameters dma_parms;
struct zfcp_fc_events events;
unsigned long next_port_scan;
struct zfcp_diag_adapter *diagnostics;
};
struct zfcp_port {
struct device dev;
struct fc_rport *rport; /* rport of fc transport class */
struct list_head list; /* list of remote ports */
struct zfcp_adapter *adapter; /* adapter used to access port */
struct list_head unit_list; /* head of logical unit list */
rwlock_t unit_list_lock; /* unit list lock */
atomic_t units; /* zfcp_unit count */
atomic_t status; /* status of this remote port */
u64 wwnn; /* WWNN if known */
u64 wwpn; /* WWPN */
u32 d_id; /* D_ID */
u32 handle; /* handle assigned by FSF */
struct zfcp_erp_action erp_action; /* pending error recovery */
atomic_t erp_counter;
u32 maxframe_size;
u32 supported_classes;
struct work_struct gid_pn_work;
struct work_struct test_link_work;
struct work_struct rport_work;
enum { RPORT_NONE, RPORT_ADD, RPORT_DEL } rport_task;
unsigned int starget_id;
};
struct zfcp_latency_record {
u32 min;
u32 max;
u64 sum;
};
struct zfcp_latency_cont {
struct zfcp_latency_record channel;
struct zfcp_latency_record fabric;
u64 counter;
};
struct zfcp_latencies {
struct zfcp_latency_cont read;
struct zfcp_latency_cont write;
struct zfcp_latency_cont cmd;
spinlock_t lock;
};
/**
* struct zfcp_unit - LUN configured via zfcp sysfs
* @dev: struct device for sysfs representation and reference counting
* @list: entry in LUN/unit list per zfcp_port
* @port: reference to zfcp_port where this LUN is configured
* @fcp_lun: 64 bit LUN value
* @scsi_work: for running scsi_scan_target
*
* This is the representation of a LUN that has been configured for
* usage. The main data here is the 64 bit LUN value, data for
* running I/O and recovery is in struct zfcp_scsi_dev.
*/
struct zfcp_unit {
struct device dev;
struct list_head list;
struct zfcp_port *port;
u64 fcp_lun;
struct work_struct scsi_work;
};
/**
* struct zfcp_scsi_dev - zfcp data per SCSI device
* @status: zfcp internal status flags
* @lun_handle: handle from "open lun" for issuing FSF requests
* @erp_action: zfcp erp data for opening and recovering this LUN
* @erp_counter: zfcp erp counter for this LUN
* @latencies: FSF channel and fabric latencies
* @port: zfcp_port where this LUN belongs to
*/
struct zfcp_scsi_dev {
atomic_t status;
u32 lun_handle;
struct zfcp_erp_action erp_action;
atomic_t erp_counter;
struct zfcp_latencies latencies;
struct zfcp_port *port;
};
/**
* sdev_to_zfcp - Access zfcp LUN data for SCSI device
* @sdev: scsi_device where to get the zfcp_scsi_dev pointer
*/
static inline struct zfcp_scsi_dev *sdev_to_zfcp(struct scsi_device *sdev)
{
return scsi_transport_device_data(sdev);
}
/**
* zfcp_scsi_dev_lun - Return SCSI device LUN as 64 bit FCP LUN
* @sdev: SCSI device where to get the LUN from
*/
static inline u64 zfcp_scsi_dev_lun(struct scsi_device *sdev)
{
u64 fcp_lun;
int_to_scsilun(sdev->lun, (struct scsi_lun *)&fcp_lun);
return fcp_lun;
}
/**
* struct zfcp_fsf_req - basic FSF request structure
* @list: list of FSF requests
* @req_id: unique request ID
* @adapter: adapter this request belongs to
* @qdio_req: qdio queue related values
* @completion: used to signal the completion of the request
* @status: status of the request
* @qtcb: associated QTCB
* @data: private data
* @timer: timer data of this request
* @erp_action: reference to erp action if request issued on behalf of ERP
* @pool: reference to memory pool if used for this request
* @issued: time when request was send (STCK)
* @handler: handler which should be called to process response
*/
struct zfcp_fsf_req {
struct list_head list;
unsigned long req_id;
struct zfcp_adapter *adapter;
struct zfcp_qdio_req qdio_req;
struct completion completion;
u32 status;
struct fsf_qtcb *qtcb;
void *data;
struct timer_list timer;
struct zfcp_erp_action *erp_action;
mempool_t *pool;
unsigned long long issued;
void (*handler)(struct zfcp_fsf_req *);
};
static inline
int zfcp_adapter_multi_buffer_active(struct zfcp_adapter *adapter)
{
return atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_MB_ACT;
}
static inline bool zfcp_fsf_req_is_status_read_buffer(struct zfcp_fsf_req *req)
{
return req->qtcb == NULL;
}
#endif /* ZFCP_DEF_H */