/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2010 Alexander Motin <mav@FreeBSD.org>
 * 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.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS 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 AUTHORS 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 _G_RAID_H_
#define _G_RAID_H_

#include <sys/param.h>
#include <sys/kobj.h>
#include <sys/bio.h>
#include <sys/time.h>
#ifdef _KERNEL
#include <sys/sysctl.h>
#endif

#define G_RAID_CLASS_NAME       "RAID"

#define G_RAID_MAGIC            "GEOM::RAID"

#define G_RAID_VERSION          0

struct g_raid_md_object;
struct g_raid_tr_object;

#define G_RAID_DEVICE_FLAG_NOAUTOSYNC   0x0000000000000001ULL
#define G_RAID_DEVICE_FLAG_NOFAILSYNC   0x0000000000000002ULL
#define G_RAID_DEVICE_FLAG_MASK (G_RAID_DEVICE_FLAG_NOAUTOSYNC | \
                                         G_RAID_DEVICE_FLAG_NOFAILSYNC)

#ifdef _KERNEL
extern u_int g_raid_aggressive_spare;
extern u_int g_raid_debug;
extern int g_raid_enable;
extern int g_raid_read_err_thresh;
extern u_int g_raid_start_timeout;
extern struct g_class g_raid_class;

#define G_RAID_DEBUG(lvl, ...) \
    _GEOM_DEBUG("GEOM_RAID", g_raid_debug, (lvl), NULL, __VA_ARGS__)
#define G_RAID_DEBUG1(lvl, sc, fmt, ...)                                \
    _GEOM_DEBUG("GEOM_RAID", g_raid_debug, (lvl), NULL, "%s: " fmt,     \
        (sc)->sc_name, ## __VA_ARGS__)
#define G_RAID_LOGREQ(lvl, bp, ...) \
    _GEOM_DEBUG("GEOM_RAID", g_raid_debug, (lvl), (bp), __VA_ARGS__)

/*
 * Flags we use to distinguish I/O initiated by the TR layer to maintain
 * the volume's characteristics, fix subdisks, extra copies of data, etc.
 *
 * G_RAID_BIO_FLAG_SYNC         I/O to update an extra copy of the data
 *                              for RAID volumes that maintain extra data
 *                              and need to rebuild that data.
 * G_RAID_BIO_FLAG_REMAP        I/O done to try to provoke a subdisk into
 *                              doing some desirable action such as bad
 *                              block remapping after we detect a bad part
 *                              of the disk.
 * G_RAID_BIO_FLAG_LOCKED       I/O holds range lock that should re released.
 *
 * and the following meta item:
 * G_RAID_BIO_FLAG_SPECIAL      And of the I/O flags that need to make it
 *                              through the range locking which would
 *                              otherwise defer the I/O until after that
 *                              range is unlocked.
 */
#define G_RAID_BIO_FLAG_SYNC            0x01
#define G_RAID_BIO_FLAG_REMAP           0x02
#define G_RAID_BIO_FLAG_SPECIAL \
                (G_RAID_BIO_FLAG_SYNC|G_RAID_BIO_FLAG_REMAP)
#define G_RAID_BIO_FLAG_LOCKED          0x80

struct g_raid_lock {
        off_t                    l_offset;
        off_t                    l_length;
        void                    *l_callback_arg;
        int                      l_pending;
        LIST_ENTRY(g_raid_lock)  l_next;
};

#define G_RAID_EVENT_WAIT       0x01
#define G_RAID_EVENT_VOLUME     0x02
#define G_RAID_EVENT_SUBDISK    0x04
#define G_RAID_EVENT_DISK       0x08
#define G_RAID_EVENT_DONE       0x10
struct g_raid_event {
        void                    *e_tgt;
        int                      e_event;
        int                      e_flags;
        int                      e_error;
        TAILQ_ENTRY(g_raid_event) e_next;
};
#define G_RAID_DISK_S_NONE              0x00    /* State is unknown. */
#define G_RAID_DISK_S_OFFLINE           0x01    /* Missing disk placeholder. */
#define G_RAID_DISK_S_DISABLED          0x02    /* Disabled. */
#define G_RAID_DISK_S_FAILED            0x03    /* Failed. */
#define G_RAID_DISK_S_STALE_FAILED      0x04    /* Old failed. */
#define G_RAID_DISK_S_SPARE             0x05    /* Hot-spare. */
#define G_RAID_DISK_S_STALE             0x06    /* Old disk, unused now. */
#define G_RAID_DISK_S_ACTIVE            0x07    /* Operational. */

#define G_RAID_DISK_E_DISCONNECTED      0x01

struct g_raid_disk {
        struct g_raid_softc     *d_softc;       /* Back-pointer to softc. */
        struct g_consumer       *d_consumer;    /* GEOM disk consumer. */
        void                    *d_md_data;     /* Disk's metadata storage. */
        int                      d_candelete;   /* BIO_DELETE supported. */
        uint64_t                 d_flags;       /* Additional flags. */
        u_int                    d_state;       /* Disk state. */
        u_int                    d_load;        /* Disk average load. */
        off_t                    d_last_offset; /* Last head offset. */
        int                      d_read_errs;   /* Count of the read errors */
        TAILQ_HEAD(, g_raid_subdisk)     d_subdisks; /* List of subdisks. */
        TAILQ_ENTRY(g_raid_disk)         d_next;        /* Next disk in the node. */
        struct g_kerneldump      d_kd;          /* Kernel dumping method/args. */
};

#define G_RAID_SUBDISK_S_NONE           0x00    /* Absent. */
#define G_RAID_SUBDISK_S_FAILED         0x01    /* Failed. */
#define G_RAID_SUBDISK_S_NEW            0x02    /* Blank. */
#define G_RAID_SUBDISK_S_REBUILD        0x03    /* Blank + rebuild. */
#define G_RAID_SUBDISK_S_UNINITIALIZED  0x04    /* Disk of the new volume. */
#define G_RAID_SUBDISK_S_STALE          0x05    /* Dirty. */
#define G_RAID_SUBDISK_S_RESYNC         0x06    /* Dirty + check/repair. */
#define G_RAID_SUBDISK_S_ACTIVE         0x07    /* Usable. */

#define G_RAID_SUBDISK_E_NEW            0x01    /* A new subdisk has arrived */
#define G_RAID_SUBDISK_E_FAILED         0x02    /* A subdisk failed, but remains in volume */
#define G_RAID_SUBDISK_E_DISCONNECTED   0x03    /* A subdisk removed from volume. */
#define G_RAID_SUBDISK_E_FIRST_TR_PRIVATE 0x80  /* translation private events */

#define G_RAID_SUBDISK_POS(sd)                                          \
    ((sd)->sd_disk ? ((sd)->sd_disk->d_last_offset - (sd)->sd_offset) : 0)
#define G_RAID_SUBDISK_TRACK_SIZE       (1 * 1024 * 1024)
#define G_RAID_SUBDISK_LOAD(sd)                                         \
    ((sd)->sd_disk ? ((sd)->sd_disk->d_load) : 0)
#define G_RAID_SUBDISK_LOAD_SCALE       256

struct g_raid_subdisk {
        struct g_raid_softc     *sd_softc;      /* Back-pointer to softc. */
        struct g_raid_disk      *sd_disk;       /* Where this subdisk lives. */
        struct g_raid_volume    *sd_volume;     /* Volume, sd is a part of. */
        off_t                    sd_offset;     /* Offset on the disk. */
        off_t                    sd_size;       /* Size on the disk. */
        u_int                    sd_pos;        /* Position in volume. */
        u_int                    sd_state;      /* Subdisk state. */
        off_t                    sd_rebuild_pos; /* Rebuild position. */
        int                      sd_recovery;   /* Count of recovery reqs. */
        TAILQ_ENTRY(g_raid_subdisk)      sd_next; /* Next subdisk on disk. */
};

#define G_RAID_MAX_SUBDISKS     16
#define G_RAID_MAX_VOLUMENAME   32

#define G_RAID_VOLUME_S_STARTING        0x00
#define G_RAID_VOLUME_S_BROKEN          0x01
#define G_RAID_VOLUME_S_DEGRADED        0x02
#define G_RAID_VOLUME_S_SUBOPTIMAL      0x03
#define G_RAID_VOLUME_S_OPTIMAL         0x04
#define G_RAID_VOLUME_S_UNSUPPORTED     0x05
#define G_RAID_VOLUME_S_STOPPED         0x06

#define G_RAID_VOLUME_S_ALIVE(s)                        \
    ((s) == G_RAID_VOLUME_S_DEGRADED ||                 \
     (s) == G_RAID_VOLUME_S_SUBOPTIMAL ||               \
     (s) == G_RAID_VOLUME_S_OPTIMAL)

#define G_RAID_VOLUME_E_DOWN            0x00
#define G_RAID_VOLUME_E_UP              0x01
#define G_RAID_VOLUME_E_START           0x10
#define G_RAID_VOLUME_E_STARTMD         0x11

#define G_RAID_VOLUME_RL_RAID0          0x00
#define G_RAID_VOLUME_RL_RAID1          0x01
#define G_RAID_VOLUME_RL_RAID3          0x03
#define G_RAID_VOLUME_RL_RAID4          0x04
#define G_RAID_VOLUME_RL_RAID5          0x05
#define G_RAID_VOLUME_RL_RAID6          0x06
#define G_RAID_VOLUME_RL_RAIDMDF        0x07
#define G_RAID_VOLUME_RL_RAID1E         0x11
#define G_RAID_VOLUME_RL_SINGLE         0x0f
#define G_RAID_VOLUME_RL_CONCAT         0x1f
#define G_RAID_VOLUME_RL_RAID5E         0x15
#define G_RAID_VOLUME_RL_RAID5EE        0x25
#define G_RAID_VOLUME_RL_RAID5R         0x35
#define G_RAID_VOLUME_RL_UNKNOWN        0xff

#define G_RAID_VOLUME_RLQ_NONE          0x00
#define G_RAID_VOLUME_RLQ_R1SM          0x00
#define G_RAID_VOLUME_RLQ_R1MM          0x01
#define G_RAID_VOLUME_RLQ_R3P0          0x00
#define G_RAID_VOLUME_RLQ_R3PN          0x01
#define G_RAID_VOLUME_RLQ_R4P0          0x00
#define G_RAID_VOLUME_RLQ_R4PN          0x01
#define G_RAID_VOLUME_RLQ_R5RA          0x00
#define G_RAID_VOLUME_RLQ_R5RS          0x01
#define G_RAID_VOLUME_RLQ_R5LA          0x02
#define G_RAID_VOLUME_RLQ_R5LS          0x03
#define G_RAID_VOLUME_RLQ_R6RA          0x00
#define G_RAID_VOLUME_RLQ_R6RS          0x01
#define G_RAID_VOLUME_RLQ_R6LA          0x02
#define G_RAID_VOLUME_RLQ_R6LS          0x03
#define G_RAID_VOLUME_RLQ_RMDFRA        0x00
#define G_RAID_VOLUME_RLQ_RMDFRS        0x01
#define G_RAID_VOLUME_RLQ_RMDFLA        0x02
#define G_RAID_VOLUME_RLQ_RMDFLS        0x03
#define G_RAID_VOLUME_RLQ_R1EA          0x00
#define G_RAID_VOLUME_RLQ_R1EO          0x01
#define G_RAID_VOLUME_RLQ_R5ERA         0x00
#define G_RAID_VOLUME_RLQ_R5ERS         0x01
#define G_RAID_VOLUME_RLQ_R5ELA         0x02
#define G_RAID_VOLUME_RLQ_R5ELS         0x03
#define G_RAID_VOLUME_RLQ_R5EERA        0x00
#define G_RAID_VOLUME_RLQ_R5EERS        0x01
#define G_RAID_VOLUME_RLQ_R5EELA        0x02
#define G_RAID_VOLUME_RLQ_R5EELS        0x03
#define G_RAID_VOLUME_RLQ_R5RRA         0x00
#define G_RAID_VOLUME_RLQ_R5RRS         0x01
#define G_RAID_VOLUME_RLQ_R5RLA         0x02
#define G_RAID_VOLUME_RLQ_R5RLS         0x03
#define G_RAID_VOLUME_RLQ_UNKNOWN       0xff

struct g_raid_volume;

struct g_raid_volume {
        struct g_raid_softc     *v_softc;       /* Back-pointer to softc. */
        struct g_provider       *v_provider;    /* GEOM provider. */
        struct g_raid_subdisk    v_subdisks[G_RAID_MAX_SUBDISKS];
                                                /* Subdisks of this volume. */
        void                    *v_md_data;     /* Volume's metadata storage. */
        struct g_raid_tr_object *v_tr;          /* Transformation object. */
        char                     v_name[G_RAID_MAX_VOLUMENAME];
                                                /* Volume name. */
        u_int                    v_state;       /* Volume state. */
        u_int                    v_raid_level;  /* Array RAID level. */
        u_int                    v_raid_level_qualifier; /* RAID level det. */
        u_int                    v_disks_count; /* Number of disks in array. */
        u_int                    v_mdf_pdisks;  /* Number of parity disks
                                                   in RAIDMDF array. */
        uint16_t                 v_mdf_polynomial; /* Polynomial for RAIDMDF. */
        uint8_t                  v_mdf_method;  /* Generation method for RAIDMDF. */
        u_int                    v_strip_size;  /* Array strip size. */
        u_int                    v_rotate_parity; /* Rotate RAID5R parity
                                                   after numer of stripes. */
        u_int                    v_sectorsize;  /* Volume sector size. */
        off_t                    v_mediasize;   /* Volume media size.  */
        struct bio_queue_head    v_inflight;    /* In-flight write requests. */
        struct bio_queue_head    v_locked;      /* Blocked I/O requests. */
        LIST_HEAD(, g_raid_lock) v_locks;        /* List of locked regions. */
        int                      v_pending_lock; /* writes to locked region */
        int                      v_dirty;       /* Volume is DIRTY. */
        struct timeval           v_last_done;   /* Time of the last I/O. */
        time_t                   v_last_write;  /* Time of the last write. */
        u_int                    v_writes;      /* Number of active writes. */
        struct root_hold_token  *v_rootmount;   /* Root mount delay token. */
        int                      v_starting;    /* Volume is starting */
        int                      v_stopping;    /* Volume is stopping */
        int                      v_provider_open; /* Number of opens. */
        int                      v_global_id;   /* Global volume ID (rX). */
        int                      v_read_only;   /* Volume is read-only. */
        TAILQ_ENTRY(g_raid_volume)       v_next; /* List of volumes entry. */
        LIST_ENTRY(g_raid_volume)        v_global_next; /* Global list entry. */
};

#define G_RAID_NODE_E_WAKE      0x00
#define G_RAID_NODE_E_START     0x01

struct g_raid_softc {
        struct g_raid_md_object *sc_md;         /* Metadata object. */
        struct g_geom           *sc_geom;       /* GEOM class instance. */
        uint64_t                 sc_flags;      /* Additional flags. */
        TAILQ_HEAD(, g_raid_volume)      sc_volumes;    /* List of volumes. */
        TAILQ_HEAD(, g_raid_disk)        sc_disks;      /* List of disks. */
        struct sx                sc_lock;       /* Main node lock. */
        struct proc             *sc_worker;     /* Worker process. */
        struct mtx               sc_queue_mtx;  /* Worker queues lock. */
        TAILQ_HEAD(, g_raid_event) sc_events;   /* Worker events queue. */
        struct bio_queue_head    sc_queue;      /* Worker I/O queue. */
        int                      sc_stopping;   /* Node is stopping */
};
#define sc_name sc_geom->name

SYSCTL_DECL(_kern_geom_raid);

/*
 * KOBJ parent class of metadata processing modules.
 */
struct g_raid_md_class {
        KOBJ_CLASS_FIELDS;
        int              mdc_enable;
        int              mdc_priority;
        LIST_ENTRY(g_raid_md_class) mdc_list;
};

/*
 * KOBJ instance of metadata processing module.
 */
struct g_raid_md_object {
        KOBJ_FIELDS;
        struct g_raid_md_class  *mdo_class;
        struct g_raid_softc     *mdo_softc;     /* Back-pointer to softc. */
};

int g_raid_md_modevent(module_t, int, void *);

#define G_RAID_MD_DECLARE(name, label)                          \
    static moduledata_t g_raid_md_##name##_mod = {              \
        "g_raid_md_" __XSTRING(name),                           \
        g_raid_md_modevent,                                     \
        &g_raid_md_##name##_class                               \
    };                                                          \
    DECLARE_MODULE(g_raid_md_##name, g_raid_md_##name##_mod,    \
        SI_SUB_DRIVERS, SI_ORDER_SECOND);                       \
    MODULE_DEPEND(g_raid_md_##name, geom_raid, 0, 0, 0);        \
    SYSCTL_NODE(_kern_geom_raid, OID_AUTO, name,                \
        CTLFLAG_RD | CTLFLAG_MPSAFE,                            \
        NULL, label " metadata module");                        \
    SYSCTL_INT(_kern_geom_raid_##name, OID_AUTO, enable,        \
        CTLFLAG_RWTUN, &g_raid_md_##name##_class.mdc_enable, 0, \
        "Enable " label " metadata format taste")

/*
 * KOBJ parent class of data transformation modules.
 */
struct g_raid_tr_class {
        KOBJ_CLASS_FIELDS;
        int              trc_enable;
        int              trc_priority;
        int              trc_accept_unmapped;
        LIST_ENTRY(g_raid_tr_class) trc_list;
};

/*
 * KOBJ instance of data transformation module.
 */
struct g_raid_tr_object {
        KOBJ_FIELDS;
        struct g_raid_tr_class  *tro_class;
        struct g_raid_volume    *tro_volume;    /* Back-pointer to volume. */
};

int g_raid_tr_modevent(module_t, int, void *);

#define G_RAID_TR_DECLARE(name, label)                          \
    static moduledata_t g_raid_tr_##name##_mod = {              \
        "g_raid_tr_" __XSTRING(name),                           \
        g_raid_tr_modevent,                                     \
        &g_raid_tr_##name##_class                               \
    };                                                          \
    DECLARE_MODULE(g_raid_tr_##name, g_raid_tr_##name##_mod,    \
        SI_SUB_DRIVERS, SI_ORDER_FIRST);                        \
    MODULE_DEPEND(g_raid_tr_##name, geom_raid, 0, 0, 0);        \
    SYSCTL_NODE(_kern_geom_raid, OID_AUTO, name,                \
        CTLFLAG_RD | CTLFLAG_MPSAFE,                            \
        NULL, label " transformation module");                  \
    SYSCTL_INT(_kern_geom_raid_##name, OID_AUTO, enable,        \
        CTLFLAG_RWTUN, &g_raid_tr_##name##_class.trc_enable, 0, \
        "Enable " label " transformation module taste")

const char * g_raid_volume_level2str(int level, int qual);
int g_raid_volume_str2level(const char *str, int *level, int *qual);
const char * g_raid_volume_state2str(int state);
const char * g_raid_subdisk_state2str(int state);
const char * g_raid_disk_state2str(int state);

struct g_raid_softc * g_raid_create_node(struct g_class *mp,
    const char *name, struct g_raid_md_object *md);
int g_raid_create_node_format(const char *format, struct gctl_req *req,
    struct g_geom **gp);
struct g_raid_volume * g_raid_create_volume(struct g_raid_softc *sc,
    const char *name, int id);
struct g_raid_disk * g_raid_create_disk(struct g_raid_softc *sc);
const char * g_raid_get_diskname(struct g_raid_disk *disk);
void g_raid_get_disk_info(struct g_raid_disk *disk);

int g_raid_start_volume(struct g_raid_volume *vol);

int g_raid_destroy_node(struct g_raid_softc *sc, int worker);
int g_raid_destroy_volume(struct g_raid_volume *vol);
int g_raid_destroy_disk(struct g_raid_disk *disk);

void g_raid_iodone(struct bio *bp, int error);
void g_raid_subdisk_iostart(struct g_raid_subdisk *sd, struct bio *bp);
int g_raid_subdisk_kerneldump(struct g_raid_subdisk *sd, void *virtual,
    off_t offset, size_t length);

struct g_consumer *g_raid_open_consumer(struct g_raid_softc *sc,
    const char *name);
void g_raid_kill_consumer(struct g_raid_softc *sc, struct g_consumer *cp);

void g_raid_report_disk_state(struct g_raid_disk *disk);
void g_raid_change_disk_state(struct g_raid_disk *disk, int state);
void g_raid_change_subdisk_state(struct g_raid_subdisk *sd, int state);
void g_raid_change_volume_state(struct g_raid_volume *vol, int state);

void g_raid_write_metadata(struct g_raid_softc *sc, struct g_raid_volume *vol,
    struct g_raid_subdisk *sd, struct g_raid_disk *disk);
void g_raid_fail_disk(struct g_raid_softc *sc,
    struct g_raid_subdisk *sd, struct g_raid_disk *disk);

void g_raid_tr_flush_common(struct g_raid_tr_object *tr, struct bio *bp);
int g_raid_tr_kerneldump_common(struct g_raid_tr_object *tr,
    void *virtual, vm_offset_t physical, off_t offset, size_t length);

u_int g_raid_ndisks(struct g_raid_softc *sc, int state);
u_int g_raid_nsubdisks(struct g_raid_volume *vol, int state);
u_int g_raid_nopens(struct g_raid_softc *sc);
struct g_raid_subdisk * g_raid_get_subdisk(struct g_raid_volume *vol,
    int state);
#define G_RAID_DESTROY_SOFT             0
#define G_RAID_DESTROY_DELAYED  1
#define G_RAID_DESTROY_HARD             2
int g_raid_destroy(struct g_raid_softc *sc, int how);
int g_raid_event_send(void *arg, int event, int flags);
int g_raid_lock_range(struct g_raid_volume *vol, off_t off, off_t len,
    struct bio *ignore, void *argp);
int g_raid_unlock_range(struct g_raid_volume *vol, off_t off, off_t len);

g_ctl_req_t g_raid_ctl;
#endif  /* _KERNEL */

#endif  /* !_G_RAID_H_ */