/* SPDX-License-Identifier: GPL-2.0 */
/*
 * linux/fs/nfs/callback.h
 *
 * Copyright (C) 2004 Trond Myklebust
 *
 * NFSv4 callback definitions
 */
#ifndef __LINUX_FS_NFS_CALLBACK_H
#define __LINUX_FS_NFS_CALLBACK_H
#include <linux/sunrpc/svc.h>

#define NFS4_CALLBACK 0x40000000
#define NFS4_CALLBACK_XDRSIZE 2048
#define NFS4_CALLBACK_BUFSIZE (1024 + NFS4_CALLBACK_XDRSIZE)

enum nfs4_callback_procnum {
        CB_NULL = 0,
        CB_COMPOUND = 1,
};

struct nfs4_slot;
struct cb_process_state {
        struct nfs_client       *clp;
        struct nfs4_slot        *slot;
        struct net              *net;
        u32                     minorversion;
        __be32                  drc_status;
        unsigned int            referring_calls;
};

struct cb_compound_hdr_arg {
        unsigned int taglen;
        const char *tag;
        unsigned int minorversion;
        unsigned int cb_ident; /* v4.0 callback identifier */
        unsigned nops;
};

struct cb_compound_hdr_res {
        __be32 *status;
        unsigned int taglen;
        const char *tag;
        __be32 *nops;
};

struct cb_getattrargs {
        struct nfs_fh fh;
        uint32_t bitmap[3];
};

struct cb_getattrres {
        __be32 status;
        uint32_t bitmap[3];
        uint64_t size;
        uint64_t change_attr;
        struct timespec64 atime;
        struct timespec64 ctime;
        struct timespec64 mtime;
};

struct cb_recallargs {
        struct nfs_fh fh;
        nfs4_stateid stateid;
        uint32_t truncate;
};

struct referring_call {
        uint32_t                        rc_sequenceid;
        uint32_t                        rc_slotid;
};

struct referring_call_list {
        struct nfs4_sessionid           rcl_sessionid;
        uint32_t                        rcl_nrefcalls;
        struct referring_call           *rcl_refcalls;
};

struct cb_sequenceargs {
        struct sockaddr                 *csa_addr;
        struct nfs4_sessionid           csa_sessionid;
        uint32_t                        csa_sequenceid;
        uint32_t                        csa_slotid;
        uint32_t                        csa_highestslotid;
        uint32_t                        csa_cachethis;
        uint32_t                        csa_nrclists;
        struct referring_call_list      *csa_rclists;
};

struct cb_sequenceres {
        __be32                          csr_status;
        struct nfs4_sessionid           csr_sessionid;
        uint32_t                        csr_sequenceid;
        uint32_t                        csr_slotid;
        uint32_t                        csr_highestslotid;
        uint32_t                        csr_target_highestslotid;
};

extern __be32 nfs4_callback_sequence(void *argp, void *resp,
                                       struct cb_process_state *cps);

#define RCA4_TYPE_MASK_RDATA_DLG        0
#define RCA4_TYPE_MASK_WDATA_DLG        1
#define RCA4_TYPE_MASK_DIR_DLG         2
#define RCA4_TYPE_MASK_FILE_LAYOUT     3
#define RCA4_TYPE_MASK_BLK_LAYOUT      4
#define RCA4_TYPE_MASK_OBJ_LAYOUT_MIN  8
#define RCA4_TYPE_MASK_OBJ_LAYOUT_MAX  9
#define RCA4_TYPE_MASK_OTHER_LAYOUT_MIN 12
#define RCA4_TYPE_MASK_OTHER_LAYOUT_MAX 15
#define PNFS_FF_RCA4_TYPE_MASK_READ 16
#define PNFS_FF_RCA4_TYPE_MASK_RW 17
#define RCA4_TYPE_MASK_ALL 0x3f31f

struct cb_recallanyargs {
        uint32_t        craa_objs_to_keep;
        uint32_t        craa_type_mask;
};

extern __be32 nfs4_callback_recallany(void *argp, void *resp,
                                        struct cb_process_state *cps);

struct cb_recallslotargs {
        uint32_t        crsa_target_highest_slotid;
};
extern __be32 nfs4_callback_recallslot(void *argp, void *resp,
                                         struct cb_process_state *cps);

struct cb_layoutrecallargs {
        uint32_t                cbl_recall_type;
        uint32_t                cbl_layout_type;
        uint32_t                cbl_layoutchanged;
        union {
                struct {
                        struct nfs_fh           cbl_fh;
                        struct pnfs_layout_range cbl_range;
                        nfs4_stateid            cbl_stateid;
                };
                struct nfs_fsid         cbl_fsid;
        };
};

extern __be32 nfs4_callback_layoutrecall(void *argp, void *resp,
                struct cb_process_state *cps);

struct cb_devicenotifyitem {
        uint32_t                cbd_notify_type;
        uint32_t                cbd_layout_type;
        struct nfs4_deviceid    cbd_dev_id;
        uint32_t                cbd_immediate;
};

struct cb_devicenotifyargs {
        uint32_t                         ndevs;
        struct cb_devicenotifyitem       *devs;
};

extern __be32 nfs4_callback_devicenotify(void *argp, void *resp,
                struct cb_process_state *cps);

struct cb_notify_lock_args {
        struct nfs_fh                   cbnl_fh;
        struct nfs_lowner               cbnl_owner;
        bool                            cbnl_valid;
};

extern __be32 nfs4_callback_notify_lock(void *argp, void *resp,
                                         struct cb_process_state *cps);
#ifdef CONFIG_NFS_V4_2
struct cb_offloadargs {
        struct nfs_fh           coa_fh;
        nfs4_stateid            coa_stateid;
        uint32_t                error;
        uint64_t                wr_count;
        struct nfs_writeverf    wr_writeverf;
};

extern __be32 nfs4_callback_offload(void *args, void *dummy,
                                    struct cb_process_state *cps);
#endif /* CONFIG_NFS_V4_2 */
extern int check_gss_callback_principal(struct nfs_client *, struct svc_rqst *);
extern __be32 nfs4_callback_getattr(void *argp, void *resp,
                                    struct cb_process_state *cps);
extern __be32 nfs4_callback_recall(void *argp, void *resp,
                                   struct cb_process_state *cps);
#if IS_ENABLED(CONFIG_NFS_V4)
extern int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt);
extern void nfs_callback_down(int minorversion, struct net *net,
                              struct rpc_xprt *xprt);
#endif /* CONFIG_NFS_V4 */
/*
 * nfs41: Callbacks are expected to not cause substantial latency,
 * so we limit their concurrency to 1 by setting up the maximum number
 * of slots for the backchannel.
 */
#define NFS41_BC_MIN_CALLBACKS 1
#define NFS41_BC_MAX_CALLBACKS 1

#define NFS4_MIN_NR_CALLBACK_THREADS 1

extern unsigned int nfs_callback_set_tcpport;
extern unsigned short nfs_callback_nr_threads;

#endif /* __LINUX_FS_NFS_CALLBACK_H */