root/sys/cam/cam_periph.h
/*-
 * Data structures and definitions for CAM peripheral ("type") drivers.
 *
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 1997, 1998 Justin T. Gibbs.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification, immediately at the beginning of the file.
 * 2. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef _CAM_CAM_PERIPH_H
#define _CAM_CAM_PERIPH_H 1

#include <sys/queue.h>
#include <cam/cam_sim.h>

#ifdef _KERNEL
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/sysctl.h>
#include <sys/taskqueue.h>

#include <vm/uma.h>

#include <cam/cam_xpt.h>

struct devstat;

extern struct cam_periph *xpt_periph;

extern struct periph_driver **periph_drivers;
void periphdriver_register(void *);
int periphdriver_unregister(void *);
void periphdriver_init(int level);

#include <sys/module.h>
#define PERIPHDRIVER_DECLARE(name, driver) \
        static int name ## _modevent(module_t mod, int type, void *data) \
        { \
                switch (type) { \
                case MOD_LOAD: \
                        periphdriver_register(data); \
                        break; \
                case MOD_UNLOAD: \
                        return (periphdriver_unregister(data)); \
                default: \
                        return EOPNOTSUPP; \
                } \
                return 0; \
        } \
        static moduledata_t name ## _mod = { \
                #name, \
                name ## _modevent, \
                (void *)&driver \
        }; \
        DECLARE_MODULE(name, name ## _mod, SI_SUB_DRIVERS, SI_ORDER_ANY); \
        MODULE_DEPEND(name, cam, 1, 1, 1)

/*
 * Callback informing the peripheral driver it can perform it's
 * initialization since the XPT is now fully initialized.
 */
typedef void (periph_init_t)(void);

/*
 * Callback requesting the peripheral driver to remove its instances
 * and shutdown, if possible.
 */
typedef int (periph_deinit_t)(void);

struct periph_driver {
        periph_init_t           *init;
        char                    *driver_name;
        TAILQ_HEAD(,cam_periph)  units;
        u_int                    generation;
        u_int                    flags;
#define CAM_PERIPH_DRV_EARLY            0x01
        periph_deinit_t         *deinit;
};

typedef enum {
        CAM_PERIPH_BIO
} cam_periph_type;

/* Generically useful offsets into the peripheral private area */
#define ppriv_ptr0 periph_priv.entries[0].ptr
#define ppriv_ptr1 periph_priv.entries[1].ptr
#define ppriv_field0 periph_priv.entries[0].field
#define ppriv_field1 periph_priv.entries[1].field

typedef void            periph_start_t (struct cam_periph *periph,
                                        union ccb *start_ccb);
typedef cam_status      periph_ctor_t (struct cam_periph *periph,
                                       void *arg);
typedef void            periph_oninv_t (struct cam_periph *periph);
typedef void            periph_dtor_t (struct cam_periph *periph);
struct cam_periph {
        periph_start_t          *periph_start;
        periph_oninv_t          *periph_oninval;
        periph_dtor_t           *periph_dtor;
        char                    *periph_name;
        struct cam_path         *path;  /* Compiled path to device */
        void                    *softc;
        struct cam_sim          *sim;
        uint32_t                 unit_number;
        cam_periph_type          type;
        uint32_t                 flags;
#define CAM_PERIPH_RUNNING              0x01
#define CAM_PERIPH_LOCKED               0x02
#define CAM_PERIPH_LOCK_WANTED          0x04
#define CAM_PERIPH_INVALID              0x08
#define CAM_PERIPH_NEW_DEV_FOUND        0x10
#define CAM_PERIPH_RECOVERY_INPROG      0x20
#define CAM_PERIPH_RUN_TASK             0x40
#define CAM_PERIPH_FREE                 0x80
#define CAM_PERIPH_ANNOUNCED            0x100
#define CAM_PERIPH_RECOVERY_WAIT        0x200
#define CAM_PERIPH_RECOVERY_WAIT_FAILED 0x400
        uint32_t                 scheduled_priority;
        uint32_t                 immediate_priority;
        int                      periph_allocating;
        int                      periph_allocated;
        uint32_t                 refcount;
        SLIST_HEAD(, ccb_hdr)    ccb_list;      /* For "immediate" requests */
        SLIST_ENTRY(cam_periph)  periph_links;
        TAILQ_ENTRY(cam_periph)  unit_links;
        ac_callback_t           *deferred_callback; 
        ac_code                  deferred_ac;
        struct task              periph_run_task;
        uma_zone_t               ccb_zone;
        struct root_hold_token   periph_rootmount;
};

#define CAM_PERIPH_MAXMAPS      2

struct cam_periph_map_info {
        int             num_bufs_used;
        void            *orig[CAM_PERIPH_MAXMAPS];
        struct buf      *bp[CAM_PERIPH_MAXMAPS];
};

cam_status cam_periph_alloc(periph_ctor_t *periph_ctor,
                            periph_oninv_t *periph_oninvalidate,
                            periph_dtor_t *periph_dtor,
                            periph_start_t *periph_start,
                            char *name, cam_periph_type type, struct cam_path *,
                            ac_callback_t *, ac_code, void *arg);
struct cam_periph *cam_periph_find(struct cam_path *path, char *name);
int             cam_periph_list(struct cam_path *, struct sbuf *);
int             cam_periph_acquire(struct cam_periph *periph);
void            cam_periph_doacquire(struct cam_periph *periph);
void            cam_periph_release(struct cam_periph *periph);
void            cam_periph_release_locked(struct cam_periph *periph);
void            cam_periph_release_locked_buses(struct cam_periph *periph);
int             cam_periph_hold(struct cam_periph *periph, int priority);
void            cam_periph_unhold(struct cam_periph *periph);
void            cam_periph_hold_boot(struct cam_periph *periph);
void            cam_periph_release_boot(struct cam_periph *periph);
void            cam_periph_invalidate(struct cam_periph *periph);
int             cam_periph_mapmem(union ccb *ccb,
                                  struct cam_periph_map_info *mapinfo,
                                  u_int maxmap);
int             cam_periph_unmapmem(union ccb *ccb,
                                    struct cam_periph_map_info *mapinfo);
union ccb       *cam_periph_getccb(struct cam_periph *periph,
                                   uint32_t priority);
int             cam_periph_runccb(union ccb *ccb,
                                  int (*error_routine)(union ccb *ccb,
                                                       cam_flags camflags,
                                                       uint32_t sense_flags),
                                  cam_flags camflags, uint32_t sense_flags,
                                  struct devstat *ds);
int             cam_periph_ioctl(struct cam_periph *periph, u_long cmd, 
                                 caddr_t addr,
                                 int (*error_routine)(union ccb *ccb,
                                                      cam_flags camflags,
                                                      uint32_t sense_flags));
void            cam_freeze_devq(struct cam_path *path);
uint32_t        cam_release_devq(struct cam_path *path, uint32_t relsim_flags,
                                 uint32_t opening_reduction, uint32_t arg,
                                 int getcount_only);
void            cam_periph_async(struct cam_periph *periph, uint32_t code,
                                 struct cam_path *path, void *arg);
void            cam_periph_bus_settle(struct cam_periph *periph,
                                      u_int bus_settle_ms);
void            cam_periph_freeze_after_event(struct cam_periph *periph,
                                              struct timeval* event_time,
                                              u_int duration_ms);
int             cam_periph_error(union ccb *ccb, cam_flags camflags,
                                 uint32_t sense_flags);
int             cam_periph_invalidate_sysctl(SYSCTL_HANDLER_ARGS);

static __inline struct mtx *
cam_periph_mtx(struct cam_periph *periph)
{
        if (periph != NULL)
                return (xpt_path_mtx(periph->path));
        else
                return (NULL);
}

#define cam_periph_owned(periph)                                        \
        mtx_owned(xpt_path_mtx((periph)->path))

#define cam_periph_lock(periph)                                         \
        mtx_lock(xpt_path_mtx((periph)->path))

#define cam_periph_unlock(periph)                                       \
        mtx_unlock(xpt_path_mtx((periph)->path))

#define cam_periph_assert(periph, what)                                 \
        mtx_assert(xpt_path_mtx((periph)->path), (what))

#define cam_periph_sleep(periph, chan, priority, wmesg, timo)           \
        xpt_path_sleep((periph)->path, (chan), (priority), (wmesg), (timo))

static inline struct cam_periph *
cam_periph_acquire_first(struct periph_driver *driver)
{
        struct cam_periph *periph;

        xpt_lock_buses();
        periph = TAILQ_FIRST(&driver->units);
        while (periph != NULL && (periph->flags & CAM_PERIPH_INVALID) != 0)
                periph = TAILQ_NEXT(periph, unit_links);
        if (periph != NULL)
                periph->refcount++;
        xpt_unlock_buses();
        return (periph);
}

static inline struct cam_periph *
cam_periph_acquire_next(struct cam_periph *pperiph)
{
        struct cam_periph *periph = pperiph;

        cam_periph_assert(pperiph, MA_NOTOWNED);
        xpt_lock_buses();
        do {
                periph = TAILQ_NEXT(periph, unit_links);
        } while (periph != NULL && (periph->flags & CAM_PERIPH_INVALID) != 0);
        if (periph != NULL)
                periph->refcount++;
        xpt_unlock_buses();
        cam_periph_release(pperiph);
        return (periph);
}

#define CAM_PERIPH_FOREACH(periph, driver)                              \
        for ((periph) = cam_periph_acquire_first(driver);               \
            (periph) != NULL;                                           \
            (periph) = cam_periph_acquire_next(periph))

#define CAM_PERIPH_PRINT(p, msg, args...)                               \
    printf("%s%d:" msg, (periph)->periph_name, (periph)->unit_number, ##args)

#endif /* _KERNEL */
#endif /* _CAM_CAM_PERIPH_H */