/* SPDX-License-Identifier: GPL-2.0 */
#ifndef S390_IO_SCH_H
#define S390_IO_SCH_H

#include <linux/types.h>
#include <asm/schid.h>
#include <asm/ccwdev.h>
#include <asm/irq.h>
#include "css.h"
#include "orb.h"

struct io_subchannel_dma_area {
        struct ccw1 sense_ccw;  /* static ccw for sense command */
};

struct io_subchannel_private {
        union orb orb;          /* operation request block */
        struct ccw_device *cdev;/* pointer to the child ccw device */
        struct {
                unsigned int suspend:1; /* allow suspend */
                unsigned int prefetch:1;/* deny prefetch */
                unsigned int inter:1;   /* suppress intermediate interrupts */
        } __packed options;
        struct io_subchannel_dma_area *dma_area;
        dma_addr_t dma_area_dma;
} __aligned(8);

#define to_io_private(n) ((struct io_subchannel_private *) \
                          dev_get_drvdata(&(n)->dev))
#define set_io_private(n, p) (dev_set_drvdata(&(n)->dev, p))

static inline struct ccw_device *sch_get_cdev(struct subchannel *sch)
{
        struct io_subchannel_private *priv = to_io_private(sch);
        return priv ? priv->cdev : NULL;
}

static inline void sch_set_cdev(struct subchannel *sch,
                                struct ccw_device *cdev)
{
        struct io_subchannel_private *priv = to_io_private(sch);
        if (priv)
                priv->cdev = cdev;
}

#define MAX_CIWS 8

/*
 * Possible status values for a CCW request's I/O.
 */
enum io_status {
        IO_DONE,
        IO_RUNNING,
        IO_STATUS_ERROR,
        IO_PATH_ERROR,
        IO_REJECTED,
        IO_KILLED
};

/**
 * ccw_request - Internal CCW request.
 * @cp: channel program to start
 * @timeout: maximum allowable time in jiffies between start I/O and interrupt
 * @maxretries: number of retries per I/O operation and path
 * @lpm: mask of paths to use
 * @check: optional callback that determines if results are final
 * @filter: optional callback to adjust request status based on IRB data
 * @callback: final callback
 * @data: user-defined pointer passed to all callbacks
 * @singlepath: if set, use only one path from @lpm per start I/O
 * @cancel: non-zero if request was cancelled
 * @done: non-zero if request was finished
 * @mask: current path mask
 * @retries: current number of retries
 * @drc: delayed return code
 */
struct ccw_request {
        struct ccw1 *cp;
        unsigned long timeout;
        u16 maxretries;
        u8 lpm;
        int (*check)(struct ccw_device *, void *);
        enum io_status (*filter)(struct ccw_device *, void *, struct irb *,
                                 enum io_status);
        void (*callback)(struct ccw_device *, void *, int);
        void *data;
        unsigned int singlepath:1;
        /* These fields are used internally. */
        unsigned int cancel:1;
        unsigned int done:1;
        u16 mask;
        u16 retries;
        int drc;
} __attribute__((packed));

/*
 * sense-id response buffer layout
 */
struct senseid {
        /* common part */
        u8  reserved;   /* always 0x'FF' */
        u16 cu_type;    /* control unit type */
        u8  cu_model;   /* control unit model */
        u16 dev_type;   /* device type */
        u8  dev_model;  /* device model */
        u8  unused;     /* padding byte */
        /* extended part */
        struct ciw ciw[MAX_CIWS];       /* variable # of CIWs */
}  __attribute__ ((packed, aligned(4)));

enum cdev_todo {
        CDEV_TODO_NOTHING,
        CDEV_TODO_ENABLE_CMF,
        CDEV_TODO_REBIND,
        CDEV_TODO_REGISTER,
        CDEV_TODO_UNREG,
        CDEV_TODO_UNREG_EVAL,
};

#define FAKE_CMD_IRB    1
#define FAKE_TM_IRB     2

struct ccw_device_dma_area {
        struct senseid senseid; /* SenseID info */
        struct ccw1 iccws[2];   /* ccws for SNID/SID/SPGID commands */
        struct irb irb;         /* device status */
        struct pgid pgid[8];    /* path group IDs per chpid*/
};

struct ccw_device_private {
        struct ccw_device *cdev;
        struct subchannel *sch;
        int state;              /* device state */
        atomic_t onoff;
        struct ccw_dev_id dev_id;       /* device id */
        struct ccw_request req;         /* internal I/O request */
        int iretry;
        u8 pgid_valid_mask;     /* mask of valid PGIDs */
        u8 pgid_todo_mask;      /* mask of PGIDs to be adjusted */
        u8 pgid_reset_mask;     /* mask of PGIDs which were reset */
        u8 path_noirq_mask;     /* mask of paths for which no irq was
                                   received */
        u8 path_notoper_mask;   /* mask of paths which were found
                                   not operable */
        u8 path_gone_mask;      /* mask of paths, that became unavailable */
        u8 path_new_mask;       /* mask of paths, that became available */
        u8 path_broken_mask;    /* mask of paths, which were found to be
                                   unusable */
        struct {
                unsigned int fast:1;    /* post with "channel end" */
                unsigned int repall:1;  /* report every interrupt status */
                unsigned int pgroup:1;  /* do path grouping */
                unsigned int force:1;   /* allow forced online */
                unsigned int mpath:1;   /* do multipathing */
        } __attribute__ ((packed)) options;
        struct {
                unsigned int esid:1;        /* Ext. SenseID supported by HW */
                unsigned int dosense:1;     /* delayed SENSE required */
                unsigned int doverify:1;    /* delayed path verification */
                unsigned int donotify:1;    /* call notify function */
                unsigned int recog_done:1;  /* dev. recog. complete */
                unsigned int fake_irb:2;    /* deliver faked irb */
                unsigned int pgroup:1;      /* pathgroup is set up */
                unsigned int mpath:1;       /* multipathing is set up */
                unsigned int pgid_unknown:1;/* unknown pgid state */
                unsigned int initialized:1; /* set if initial reference held */
        } __attribute__((packed)) flags;
        unsigned long intparm;  /* user interruption parameter */
        struct qdio_irq *qdio_data;
        int async_kill_io_rc;
        struct work_struct todo_work;
        enum cdev_todo todo;
        wait_queue_head_t wait_q;
        struct timer_list timer;
        void *cmb;                      /* measurement information */
        struct list_head cmb_list;      /* list of measured devices */
        u64 cmb_start_time;             /* clock value of cmb reset */
        void *cmb_wait;                 /* deferred cmb enable/disable */
        struct gen_pool *dma_pool;
        struct ccw_device_dma_area *dma_area;
        enum interruption_class int_class;
};

#endif