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

#include <linux/bitrev.h>
#include <linux/completion.h>
#include <linux/kref.h>
#include <linux/mempool.h>
#include <linux/rbtree.h>
#include <linux/refcount.h>
#include <linux/ktime.h>

#include <linux/ceph/types.h>
#include <linux/ceph/osdmap.h>
#include <linux/ceph/messenger.h>
#include <linux/ceph/msgpool.h>
#include <linux/ceph/auth.h>
#include <linux/ceph/pagelist.h>

struct ceph_msg;
struct ceph_snap_context;
struct ceph_osd_request;
struct ceph_osd_client;

/*
 * completion callback for async writepages
 */
typedef void (*ceph_osdc_callback_t)(struct ceph_osd_request *);

#define CEPH_HOMELESS_OSD       -1

/*
 * A single extent in a SPARSE_READ reply.
 *
 * Note that these come from the OSD as little-endian values. On BE arches,
 * we convert them in-place after receipt.
 */
struct ceph_sparse_extent {
        u64     off;
        u64     len;
} __packed;

/* Sparse read state machine state values */
enum ceph_sparse_read_state {
        CEPH_SPARSE_READ_HDR    = 0,
        CEPH_SPARSE_READ_EXTENTS,
        CEPH_SPARSE_READ_DATA_LEN,
        CEPH_SPARSE_READ_DATA_PRE,
        CEPH_SPARSE_READ_DATA,
};

/*
 * A SPARSE_READ reply is a 32-bit count of extents, followed by an array of
 * 64-bit offset/length pairs, and then all of the actual file data
 * concatenated after it (sans holes).
 *
 * Unfortunately, we don't know how long the extent array is until we've
 * started reading the data section of the reply. The caller should send down
 * a destination buffer for the array, but we'll alloc one if it's too small
 * or if the caller doesn't.
 */
struct ceph_sparse_read {
        enum ceph_sparse_read_state     sr_state;    /* state machine state */
        u64                             sr_req_off;  /* orig request offset */
        u64                             sr_req_len;  /* orig request length */
        u64                             sr_pos;      /* current pos in buffer */
        int                             sr_index;    /* current extent index */
        u32                             sr_datalen;  /* length of actual data */
        u32                             sr_count;    /* extent count in reply */
        int                             sr_ext_len;  /* length of extent array */
        struct ceph_sparse_extent       *sr_extent;  /* extent array */
};

/*
 * A given osd we're communicating with.
 *
 * Note that the o_requests tree can be searched while holding the "lock" mutex
 * or the "o_requests_lock" spinlock. Insertion or removal requires both!
 */
struct ceph_osd {
        refcount_t o_ref;
        int o_sparse_op_idx;
        struct ceph_osd_client *o_osdc;
        int o_osd;
        int o_incarnation;
        struct rb_node o_node;
        struct ceph_connection o_con;
        spinlock_t o_requests_lock;
        struct rb_root o_requests;
        struct rb_root o_linger_requests;
        struct rb_root o_backoff_mappings;
        struct rb_root o_backoffs_by_id;
        struct list_head o_osd_lru;
        struct ceph_auth_handshake o_auth;
        unsigned long lru_ttl;
        struct list_head o_keepalive_item;
        struct mutex lock;
        struct ceph_sparse_read o_sparse_read;
};

#define CEPH_OSD_SLAB_OPS       2
#define CEPH_OSD_MAX_OPS        16

enum ceph_osd_data_type {
        CEPH_OSD_DATA_TYPE_NONE = 0,
        CEPH_OSD_DATA_TYPE_PAGES,
        CEPH_OSD_DATA_TYPE_PAGELIST,
#ifdef CONFIG_BLOCK
        CEPH_OSD_DATA_TYPE_BIO,
#endif /* CONFIG_BLOCK */
        CEPH_OSD_DATA_TYPE_BVECS,
        CEPH_OSD_DATA_TYPE_ITER,
};

struct ceph_osd_data {
        enum ceph_osd_data_type type;
        union {
                struct {
                        struct page     **pages;
                        u64             length;
                        u32             alignment;
                        bool            pages_from_pool;
                        bool            own_pages;
                };
                struct ceph_pagelist    *pagelist;
#ifdef CONFIG_BLOCK
                struct {
                        struct ceph_bio_iter    bio_pos;
                        u32                     bio_length;
                };
#endif /* CONFIG_BLOCK */
                struct {
                        struct ceph_bvec_iter   bvec_pos;
                        u32                     num_bvecs;
                };
                struct iov_iter         iter;
        };
};

struct ceph_osd_req_op {
        u16 op;           /* CEPH_OSD_OP_* */
        u32 flags;        /* CEPH_OSD_OP_FLAG_* */
        u32 indata_len;   /* request */
        u32 outdata_len;  /* reply */
        s32 rval;

        union {
                struct ceph_osd_data raw_data_in;
                struct {
                        u64 offset, length;
                        u64 truncate_size;
                        u32 truncate_seq;
                        int sparse_ext_cnt;
                        struct ceph_sparse_extent *sparse_ext;
                        struct ceph_osd_data osd_data;
                } extent;
                struct {
                        u32 name_len;
                        u32 value_len;
                        __u8 cmp_op;       /* CEPH_OSD_CMPXATTR_OP_* */
                        __u8 cmp_mode;     /* CEPH_OSD_CMPXATTR_MODE_* */
                        struct ceph_osd_data osd_data;
                } xattr;
                struct {
                        const char *class_name;
                        const char *method_name;
                        struct ceph_osd_data request_info;
                        struct ceph_osd_data request_data;
                        struct ceph_osd_data response_data;
                        __u8 class_len;
                        __u8 method_len;
                        u32 indata_len;
                } cls;
                struct {
                        u64 cookie;
                        __u8 op;           /* CEPH_OSD_WATCH_OP_ */
                        u32 gen;
                } watch;
                struct {
                        struct ceph_osd_data request_data;
                } notify_ack;
                struct {
                        u64 cookie;
                        struct ceph_osd_data request_data;
                        struct ceph_osd_data response_data;
                } notify;
                struct {
                        struct ceph_osd_data response_data;
                } list_watchers;
                struct {
                        u64 expected_object_size;
                        u64 expected_write_size;
                        u32 flags;  /* CEPH_OSD_OP_ALLOC_HINT_FLAG_* */
                } alloc_hint;
                struct {
                        u64 snapid;
                        u64 src_version;
                        u8 flags;
                        u32 src_fadvise_flags;
                        struct ceph_osd_data osd_data;
                } copy_from;
                struct {
                        u64 ver;
                } assert_ver;
        };
};

struct ceph_osd_request_target {
        struct ceph_object_id base_oid;
        struct ceph_object_locator base_oloc;
        struct ceph_object_id target_oid;
        struct ceph_object_locator target_oloc;

        struct ceph_pg pgid;               /* last raw pg we mapped to */
        struct ceph_spg spgid;             /* last actual spg we mapped to */
        u32 pg_num;
        u32 pg_num_mask;
        struct ceph_osds acting;
        struct ceph_osds up;
        int size;
        int min_size;
        bool sort_bitwise;
        bool recovery_deletes;

        unsigned int flags;                /* CEPH_OSD_FLAG_* */
        bool used_replica;
        bool paused;

        u32 epoch;
        u32 last_force_resend;

        int osd;
};

/* an in-flight request */
struct ceph_osd_request {
        u64             r_tid;              /* unique for this client */
        struct rb_node  r_node;
        struct rb_node  r_mc_node;          /* map check */
        struct work_struct r_complete_work;
        struct ceph_osd *r_osd;

        struct ceph_osd_request_target r_t;
#define r_base_oid      r_t.base_oid
#define r_base_oloc     r_t.base_oloc
#define r_flags         r_t.flags

        struct ceph_msg  *r_request, *r_reply;
        u32               r_sent;      /* >0 if r_request is sending/sent */

        /* request osd ops array  */
        unsigned int            r_num_ops;

        int               r_result;

        struct ceph_osd_client *r_osdc;
        struct kref       r_kref;
        bool              r_mempool;
        bool              r_linger;           /* don't resend on failure */
        struct completion r_completion;       /* private to osd_client.c */
        ceph_osdc_callback_t r_callback;

        struct inode *r_inode;                /* for use by callbacks */
        struct list_head r_private_item;      /* ditto */
        void *r_priv;                         /* ditto */

        /* set by submitter */
        u64 r_snapid;                         /* for reads, CEPH_NOSNAP o/w */
        struct ceph_snap_context *r_snapc;    /* for writes */
        struct timespec64 r_mtime;            /* ditto */
        u64 r_data_offset;                    /* ditto */

        /* internal */
        u64 r_version;                        /* data version sent in reply */
        unsigned long r_stamp;                /* jiffies, send or check time */
        unsigned long r_start_stamp;          /* jiffies */
        ktime_t r_start_latency;              /* ktime_t */
        ktime_t r_end_latency;                /* ktime_t */
        int r_attempts;
        u32 r_map_dne_bound;

        struct ceph_osd_req_op r_ops[] __counted_by(r_num_ops);
};

struct ceph_request_redirect {
        struct ceph_object_locator oloc;
};

/*
 * osd request identifier
 *
 * caller name + incarnation# + tid to unique identify this request
 */
struct ceph_osd_reqid {
        struct ceph_entity_name name;
        __le64 tid;
        __le32 inc;
} __packed;

struct ceph_blkin_trace_info {
        __le64 trace_id;
        __le64 span_id;
        __le64 parent_span_id;
} __packed;

typedef void (*rados_watchcb2_t)(void *arg, u64 notify_id, u64 cookie,
                                 u64 notifier_id, void *data, size_t data_len);
typedef void (*rados_watcherrcb_t)(void *arg, u64 cookie, int err);

struct ceph_osd_linger_request {
        struct ceph_osd_client *osdc;
        u64 linger_id;
        bool committed;
        bool is_watch;                  /* watch or notify */

        struct ceph_osd *osd;
        struct ceph_osd_request *reg_req;
        struct ceph_osd_request *ping_req;
        unsigned long ping_sent;
        unsigned long watch_valid_thru;
        struct list_head pending_lworks;

        struct ceph_osd_request_target t;
        u32 map_dne_bound;

        struct timespec64 mtime;

        struct kref kref;
        struct mutex lock;
        struct rb_node node;            /* osd */
        struct rb_node osdc_node;       /* osdc */
        struct rb_node mc_node;         /* map check */
        struct list_head scan_item;

        struct completion reg_commit_wait;
        struct completion notify_finish_wait;
        int reg_commit_error;
        int notify_finish_error;
        int last_error;

        u32 register_gen;
        u64 notify_id;

        rados_watchcb2_t wcb;
        rados_watcherrcb_t errcb;
        void *data;

        struct ceph_pagelist *request_pl;
        struct page **notify_id_pages;

        struct page ***preply_pages;
        size_t *preply_len;
};

struct ceph_watch_item {
        struct ceph_entity_name name;
        u64 cookie;
        struct ceph_entity_addr addr;
};

struct ceph_spg_mapping {
        struct rb_node node;
        struct ceph_spg spgid;

        struct rb_root backoffs;
};

struct ceph_hobject_id {
        void *key;
        size_t key_len;
        void *oid;
        size_t oid_len;
        u64 snapid;
        u32 hash;
        u8 is_max;
        void *nspace;
        size_t nspace_len;
        s64 pool;

        /* cache */
        u32 hash_reverse_bits;
};

static inline void ceph_hoid_build_hash_cache(struct ceph_hobject_id *hoid)
{
        hoid->hash_reverse_bits = bitrev32(hoid->hash);
}

/*
 * PG-wide backoff: [begin, end)
 * per-object backoff: begin == end
 */
struct ceph_osd_backoff {
        struct rb_node spg_node;
        struct rb_node id_node;

        struct ceph_spg spgid;
        u64 id;
        struct ceph_hobject_id *begin;
        struct ceph_hobject_id *end;
};

#define CEPH_LINGER_ID_START    0xffff000000000000ULL

struct ceph_osd_client {
        struct ceph_client     *client;

        struct ceph_osdmap     *osdmap;       /* current map */
        struct rw_semaphore    lock;

        struct rb_root         osds;          /* osds */
        struct list_head       osd_lru;       /* idle osds */
        spinlock_t             osd_lru_lock;
        u32                    epoch_barrier;
        struct ceph_osd        homeless_osd;
        atomic64_t             last_tid;      /* tid of last request */
        u64                    last_linger_id;
        struct rb_root         linger_requests; /* lingering requests */
        struct rb_root         map_checks;
        struct rb_root         linger_map_checks;
        atomic_t               num_requests;
        atomic_t               num_homeless;
        int                    abort_err;
        struct delayed_work    timeout_work;
        struct delayed_work    osds_timeout_work;
#ifdef CONFIG_DEBUG_FS
        struct dentry          *debugfs_file;
#endif

        mempool_t              *req_mempool;

        struct ceph_msgpool     msgpool_op;
        struct ceph_msgpool     msgpool_op_reply;

        struct workqueue_struct *notify_wq;
        struct workqueue_struct *completion_wq;
};

static inline bool ceph_osdmap_flag(struct ceph_osd_client *osdc, int flag)
{
        return osdc->osdmap->flags & flag;
}

extern int ceph_osdc_setup(void);
extern void ceph_osdc_cleanup(void);

extern int ceph_osdc_init(struct ceph_osd_client *osdc,
                          struct ceph_client *client);
extern void ceph_osdc_stop(struct ceph_osd_client *osdc);
extern void ceph_osdc_reopen_osds(struct ceph_osd_client *osdc);

extern void ceph_osdc_handle_map(struct ceph_osd_client *osdc,
                                 struct ceph_msg *msg);
void ceph_osdc_update_epoch_barrier(struct ceph_osd_client *osdc, u32 eb);
void ceph_osdc_abort_requests(struct ceph_osd_client *osdc, int err);
void ceph_osdc_clear_abort_err(struct ceph_osd_client *osdc);

#define osd_req_op_data(oreq, whch, typ, fld)                           \
({                                                                      \
        struct ceph_osd_request *__oreq = (oreq);                       \
        unsigned int __whch = (whch);                                   \
        BUG_ON(__whch >= __oreq->r_num_ops);                            \
        &__oreq->r_ops[__whch].typ.fld;                                 \
})

struct ceph_osd_req_op *osd_req_op_init(struct ceph_osd_request *osd_req,
                            unsigned int which, u16 opcode, u32 flags);

extern void osd_req_op_raw_data_in_pages(struct ceph_osd_request *,
                                        unsigned int which,
                                        struct page **pages, u64 length,
                                        u32 alignment, bool pages_from_pool,
                                        bool own_pages);

extern void osd_req_op_extent_init(struct ceph_osd_request *osd_req,
                                        unsigned int which, u16 opcode,
                                        u64 offset, u64 length,
                                        u64 truncate_size, u32 truncate_seq);
extern void osd_req_op_extent_update(struct ceph_osd_request *osd_req,
                                        unsigned int which, u64 length);
extern void osd_req_op_extent_dup_last(struct ceph_osd_request *osd_req,
                                       unsigned int which, u64 offset_inc);

extern struct ceph_osd_data *osd_req_op_extent_osd_data(
                                        struct ceph_osd_request *osd_req,
                                        unsigned int which);

extern void osd_req_op_extent_osd_data_pages(struct ceph_osd_request *,
                                        unsigned int which,
                                        struct page **pages, u64 length,
                                        u32 alignment, bool pages_from_pool,
                                        bool own_pages);
#ifdef CONFIG_BLOCK
void osd_req_op_extent_osd_data_bio(struct ceph_osd_request *osd_req,
                                    unsigned int which,
                                    struct ceph_bio_iter *bio_pos,
                                    u32 bio_length);
#endif /* CONFIG_BLOCK */
void osd_req_op_extent_osd_data_bvecs(struct ceph_osd_request *osd_req,
                                      unsigned int which,
                                      struct bio_vec *bvecs, u32 num_bvecs,
                                      u32 bytes);
void osd_req_op_extent_osd_data_bvec_pos(struct ceph_osd_request *osd_req,
                                         unsigned int which,
                                         struct ceph_bvec_iter *bvec_pos);
void osd_req_op_extent_osd_iter(struct ceph_osd_request *osd_req,
                                unsigned int which, struct iov_iter *iter);

extern void osd_req_op_cls_request_data_pages(struct ceph_osd_request *,
                                        unsigned int which,
                                        struct page **pages, u64 length,
                                        u32 alignment, bool pages_from_pool,
                                        bool own_pages);
void osd_req_op_cls_request_data_bvecs(struct ceph_osd_request *osd_req,
                                       unsigned int which,
                                       struct bio_vec *bvecs, u32 num_bvecs,
                                       u32 bytes);
extern void osd_req_op_cls_response_data_pages(struct ceph_osd_request *,
                                        unsigned int which,
                                        struct page **pages, u64 length,
                                        u32 alignment, bool pages_from_pool,
                                        bool own_pages);
int osd_req_op_cls_init(struct ceph_osd_request *osd_req, unsigned int which,
                        const char *class, const char *method);
extern int osd_req_op_xattr_init(struct ceph_osd_request *osd_req, unsigned int which,
                                 u16 opcode, const char *name, const void *value,
                                 size_t size, u8 cmp_op, u8 cmp_mode);
extern void osd_req_op_alloc_hint_init(struct ceph_osd_request *osd_req,
                                       unsigned int which,
                                       u64 expected_object_size,
                                       u64 expected_write_size,
                                       u32 flags);
extern int osd_req_op_copy_from_init(struct ceph_osd_request *req,
                                     u64 src_snapid, u64 src_version,
                                     struct ceph_object_id *src_oid,
                                     struct ceph_object_locator *src_oloc,
                                     u32 src_fadvise_flags,
                                     u32 dst_fadvise_flags,
                                     u32 truncate_seq, u64 truncate_size,
                                     u8 copy_from_flags);

extern struct ceph_osd_request *ceph_osdc_alloc_request(struct ceph_osd_client *osdc,
                                               struct ceph_snap_context *snapc,
                                               unsigned int num_ops,
                                               bool use_mempool,
                                               gfp_t gfp_flags);
int ceph_osdc_alloc_messages(struct ceph_osd_request *req, gfp_t gfp);

extern struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *,
                                      struct ceph_file_layout *layout,
                                      struct ceph_vino vino,
                                      u64 offset, u64 *len,
                                      unsigned int which, int num_ops,
                                      int opcode, int flags,
                                      struct ceph_snap_context *snapc,
                                      u32 truncate_seq, u64 truncate_size,
                                      bool use_mempool);

int __ceph_alloc_sparse_ext_map(struct ceph_osd_req_op *op, int cnt);

/*
 * How big an extent array should we preallocate for a sparse read? This is
 * just a starting value.  If we get more than this back from the OSD, the
 * receiver will reallocate.
 */
#define CEPH_SPARSE_EXT_ARRAY_INITIAL  16

static inline int ceph_alloc_sparse_ext_map(struct ceph_osd_req_op *op, int cnt)
{
        if (!cnt)
                cnt = CEPH_SPARSE_EXT_ARRAY_INITIAL;

        return __ceph_alloc_sparse_ext_map(op, cnt);
}

extern void ceph_osdc_get_request(struct ceph_osd_request *req);
extern void ceph_osdc_put_request(struct ceph_osd_request *req);

void ceph_osdc_start_request(struct ceph_osd_client *osdc,
                             struct ceph_osd_request *req);
extern void ceph_osdc_cancel_request(struct ceph_osd_request *req);
extern int ceph_osdc_wait_request(struct ceph_osd_client *osdc,
                                  struct ceph_osd_request *req);
extern void ceph_osdc_sync(struct ceph_osd_client *osdc);

extern void ceph_osdc_flush_notifies(struct ceph_osd_client *osdc);
void ceph_osdc_maybe_request_map(struct ceph_osd_client *osdc);

int ceph_osdc_call(struct ceph_osd_client *osdc,
                   struct ceph_object_id *oid,
                   struct ceph_object_locator *oloc,
                   const char *class, const char *method,
                   unsigned int flags,
                   struct page *req_page, size_t req_len,
                   struct page **resp_pages, size_t *resp_len);

/* watch/notify */
struct ceph_osd_linger_request *
ceph_osdc_watch(struct ceph_osd_client *osdc,
                struct ceph_object_id *oid,
                struct ceph_object_locator *oloc,
                rados_watchcb2_t wcb,
                rados_watcherrcb_t errcb,
                void *data);
int ceph_osdc_unwatch(struct ceph_osd_client *osdc,
                      struct ceph_osd_linger_request *lreq);

int ceph_osdc_notify_ack(struct ceph_osd_client *osdc,
                         struct ceph_object_id *oid,
                         struct ceph_object_locator *oloc,
                         u64 notify_id,
                         u64 cookie,
                         void *payload,
                         u32 payload_len);
int ceph_osdc_notify(struct ceph_osd_client *osdc,
                     struct ceph_object_id *oid,
                     struct ceph_object_locator *oloc,
                     void *payload,
                     u32 payload_len,
                     u32 timeout,
                     struct page ***preply_pages,
                     size_t *preply_len);
int ceph_osdc_list_watchers(struct ceph_osd_client *osdc,
                            struct ceph_object_id *oid,
                            struct ceph_object_locator *oloc,
                            struct ceph_watch_item **watchers,
                            u32 *num_watchers);

/* Find offset into the buffer of the end of the extent map */
static inline u64 ceph_sparse_ext_map_end(struct ceph_osd_req_op *op)
{
        struct ceph_sparse_extent *ext;

        /* No extents? No data */
        if (op->extent.sparse_ext_cnt == 0)
                return 0;

        ext = &op->extent.sparse_ext[op->extent.sparse_ext_cnt - 1];

        return ext->off + ext->len - op->extent.offset;
}

#endif