state.h

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/*
 *  Copyright (c) 2001 The Regents of the University of Michigan.
 *  All rights reserved.
 *
 *  Kendrick Smith <[email protected]>
 *  Andy Adamson <[email protected]>
 *  
 *  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.
 *  3. Neither the name of the University nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED ``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 REGENTS 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 _NFSD4_STATE_H
#define _NFSD4_STATE_H

#include <linux/idr.h>
#include <linux/sunrpc/svc_xprt.h>
#include <linux/nfsd/nfsfh.h>
#include "nfsfh.h"

typedef struct {
    u32             cl_boot;
    u32             cl_id;
} clientid_t;

typedef struct {
    clientid_t  so_clid;
    u32     so_id;
} stateid_opaque_t;

typedef struct {
    u32                     si_generation;
    stateid_opaque_t        si_opaque;
} stateid_t;

#define STATEID_FMT "(%08x/%08x/%08x/%08x)"
#define STATEID_VAL(s) \
    (s)->si_opaque.so_clid.cl_boot, \
    (s)->si_opaque.so_clid.cl_id, \
    (s)->si_opaque.so_id, \
    (s)->si_generation

struct nfsd4_callback {
    void *cb_op;
    struct nfs4_client *cb_clp;
    struct list_head cb_per_client;
    u32 cb_minorversion;
    struct rpc_message cb_msg;
    const struct rpc_call_ops *cb_ops;
    struct work_struct cb_work;
    bool cb_done;
};

struct nfs4_stid {
#define NFS4_OPEN_STID 1
#define NFS4_LOCK_STID 2
#define NFS4_DELEG_STID 4
/* For an open stateid kept around *only* to process close replays: */
#define NFS4_CLOSED_STID 8
    unsigned char sc_type;
    stateid_t sc_stateid;
    struct nfs4_client *sc_client;
};

struct nfs4_delegation {
    struct nfs4_stid    dl_stid; /* must be first field */
    struct list_head    dl_perfile;
    struct list_head    dl_perclnt;
    struct list_head    dl_recall_lru;  /* delegation recalled */
    atomic_t        dl_count;       /* ref count */
    struct nfs4_file    *dl_file;
    u32         dl_type;
    time_t          dl_time;
/* For recall: */
    struct knfsd_fh     dl_fh;
    int         dl_retries;
    struct nfsd4_callback   dl_recall;
};

/* client delegation callback info */
struct nfs4_cb_conn {
    /* SETCLIENTID info */
    struct sockaddr_storage cb_addr;
    struct sockaddr_storage cb_saddr;
    size_t          cb_addrlen;
    u32                     cb_prog; /* used only in 4.0 case;
                        per-session otherwise */
    u32                     cb_ident;   /* minorversion 0 only */
    struct svc_xprt     *cb_xprt;   /* minorversion 1 only */
};

static inline struct nfs4_delegation *delegstateid(struct nfs4_stid *s)
{
    return container_of(s, struct nfs4_delegation, dl_stid);
}

/* Maximum number of slots per session. 160 is useful for long haul TCP */
#define NFSD_MAX_SLOTS_PER_SESSION     160
/* Maximum number of operations per session compound */
#define NFSD_MAX_OPS_PER_COMPOUND   16
/* Maximum  session per slot cache size */
#define NFSD_SLOT_CACHE_SIZE        1024
/* Maximum number of NFSD_SLOT_CACHE_SIZE slots per session */
#define NFSD_CACHE_SIZE_SLOTS_PER_SESSION   32
#define NFSD_MAX_MEM_PER_SESSION  \
        (NFSD_CACHE_SIZE_SLOTS_PER_SESSION * NFSD_SLOT_CACHE_SIZE)

struct nfsd4_slot {
    u32 sl_seqid;
    __be32  sl_status;
    u32 sl_datalen;
    u16 sl_opcnt;
#define NFSD4_SLOT_INUSE    (1 << 0)
#define NFSD4_SLOT_CACHETHIS    (1 << 1)
#define NFSD4_SLOT_INITIALIZED  (1 << 2)
    u8  sl_flags;
    char    sl_data[];
};

struct nfsd4_channel_attrs {
    u32     headerpadsz;
    u32     maxreq_sz;
    u32     maxresp_sz;
    u32     maxresp_cached;
    u32     maxops;
    u32     maxreqs;
    u32     nr_rdma_attrs;
    u32     rdma_attrs;
};

struct nfsd4_create_session {
    clientid_t          clientid;
    struct nfs4_sessionid       sessionid;
    u32             seqid;
    u32             flags;
    struct nfsd4_channel_attrs  fore_channel;
    struct nfsd4_channel_attrs  back_channel;
    u32             callback_prog;
    u32             uid;
    u32             gid;
};

struct nfsd4_bind_conn_to_session {
    struct nfs4_sessionid       sessionid;
    u32             dir;
};

/* The single slot clientid cache structure */
struct nfsd4_clid_slot {
    u32             sl_seqid;
    __be32              sl_status;
    struct nfsd4_create_session sl_cr_ses;
};

struct nfsd4_conn {
    struct list_head cn_persession;
    struct svc_xprt *cn_xprt;
    struct svc_xpt_user cn_xpt_user;
    struct nfsd4_session *cn_session;
/* CDFC4_FORE, CDFC4_BACK: */
    unsigned char cn_flags;
};

struct nfsd4_session {
    struct kref     se_ref;
    struct list_head    se_hash;    /* hash by sessionid */
    struct list_head    se_perclnt;
    u32         se_flags;
    struct nfs4_client  *se_client;
    struct nfs4_sessionid   se_sessionid;
    struct nfsd4_channel_attrs se_fchannel;
    struct nfsd4_channel_attrs se_bchannel;
    struct list_head    se_conns;
    u32         se_cb_prog;
    u32         se_cb_seq_nr;
    struct nfsd4_slot   *se_slots[];    /* forward channel slots */
};

extern void nfsd4_put_session(struct nfsd4_session *ses);

/* formatted contents of nfs4_sessionid */
struct nfsd4_sessionid {
    clientid_t  clientid;
    u32     sequence;
    u32     reserved;
};

#define HEXDIR_LEN     33 /* hex version of 16 byte md5 of cl_name plus '\0' */

/*
 * struct nfs4_client - one per client.  Clientids live here.
 *  o Each nfs4_client is hashed by clientid.
 *
 *  o Each nfs4_clients is also hashed by name 
 *    (the opaque quantity initially sent by the client to identify itself).
 *    
 *  o cl_perclient list is used to ensure no dangling stateowner references
 *    when we expire the nfs4_client
 */
struct nfs4_client {
    struct list_head    cl_idhash;  /* hash by cl_clientid.id */
    struct list_head    cl_strhash;     /* hash by cl_name */
    struct list_head    cl_openowners;
    struct idr      cl_stateids;    /* stateid lookup */
    struct list_head    cl_delegations;
    struct list_head        cl_lru;         /* tail queue */
    struct xdr_netobj   cl_name;    /* id generated by client */
    char                    cl_recdir[HEXDIR_LEN]; /* recovery dir */
    nfs4_verifier       cl_verifier;    /* generated by client */
    time_t                  cl_time;        /* time of last lease renewal */
    struct sockaddr_storage cl_addr;    /* client ipaddress */
    struct svc_cred     cl_cred;    /* setclientid principal */
    clientid_t      cl_clientid;    /* generated by server */
    nfs4_verifier       cl_confirm; /* generated by server */
    u32         cl_minorversion;

    /* for v4.0 and v4.1 callbacks: */
    struct nfs4_cb_conn cl_cb_conn;
#define NFSD4_CLIENT_CB_UPDATE      (0)
#define NFSD4_CLIENT_CB_KILL        (1)
#define NFSD4_CLIENT_STABLE     (2) /* client on stable storage */
#define NFSD4_CLIENT_RECLAIM_COMPLETE   (3) /* reclaim_complete done */
#define NFSD4_CLIENT_CB_FLAG_MASK   (1 << NFSD4_CLIENT_CB_UPDATE | \
                     1 << NFSD4_CLIENT_CB_KILL)
    unsigned long       cl_flags;
    struct rpc_clnt     *cl_cb_client;
    u32         cl_cb_ident;
#define NFSD4_CB_UP     0
#define NFSD4_CB_UNKNOWN    1
#define NFSD4_CB_DOWN       2
#define NFSD4_CB_FAULT      3
    int         cl_cb_state;
    struct nfsd4_callback   cl_cb_null;
    struct nfsd4_session    *cl_cb_session;
    struct list_head    cl_callbacks; /* list of in-progress callbacks */

    /* for all client information that callback code might need: */
    spinlock_t      cl_lock;

    /* for nfs41 */
    struct list_head    cl_sessions;
    struct nfsd4_clid_slot  cl_cs_slot; /* create_session slot */
    u32         cl_exchange_flags;
    /* number of rpc's in progress over an associated session: */
    atomic_t        cl_refcount;

    /* for nfs41 callbacks */
    /* We currently support a single back channel with a single slot */
    unsigned long       cl_cb_slot_busy;
    struct rpc_wait_queue   cl_cb_waitq;    /* backchannel callers may */
                        /* wait here for slots */
};

static inline void
mark_client_expired(struct nfs4_client *clp)
{
    clp->cl_time = 0;
}

static inline bool
is_client_expired(struct nfs4_client *clp)
{
    return clp->cl_time == 0;
}

/* struct nfs4_client_reset
 * one per old client. Populates reset_str_hashtbl. Filled from conf_id_hashtbl
 * upon lease reset, or from upcall to state_daemon (to read in state
 * from non-volitile storage) upon reboot.
 */
struct nfs4_client_reclaim {
    struct list_head    cr_strhash; /* hash by cr_name */
    char            cr_recdir[HEXDIR_LEN]; /* recover dir */
};

static inline void
update_stateid(stateid_t *stateid)
{
    stateid->si_generation++;
    /* Wraparound recommendation from 3530bis-13 9.1.3.2: */
    if (stateid->si_generation == 0)
        stateid->si_generation = 1;
}

/* A reasonable value for REPLAY_ISIZE was estimated as follows:  
 * The OPEN response, typically the largest, requires 
 *   4(status) + 8(stateid) + 20(changeinfo) + 4(rflags) +  8(verifier) + 
 *   4(deleg. type) + 8(deleg. stateid) + 4(deleg. recall flag) + 
 *   20(deleg. space limit) + ~32(deleg. ace) = 112 bytes 
 */

#define NFSD4_REPLAY_ISIZE       112 

/*
 * Replay buffer, where the result of the last seqid-mutating operation 
 * is cached. 
 */
struct nfs4_replay {
    __be32          rp_status;
    unsigned int        rp_buflen;
    char            *rp_buf;
    struct knfsd_fh     rp_openfh;
    char            rp_ibuf[NFSD4_REPLAY_ISIZE];
};

struct nfs4_stateowner {
    struct list_head        so_strhash;   /* hash by op_name */
    struct list_head        so_stateids;
    struct nfs4_client *    so_client;
    /* after increment in ENCODE_SEQID_OP_TAIL, represents the next
     * sequence id expected from the client: */
    u32                     so_seqid;
    struct xdr_netobj       so_owner;     /* open owner name */
    struct nfs4_replay  so_replay;
    bool            so_is_open_owner;
};

struct nfs4_openowner {
    struct nfs4_stateowner  oo_owner; /* must be first field */
    struct list_head        oo_perclient;
    /*
     * We keep around openowners a little while after last close,
     * which saves clients from having to confirm, and allows us to
     * handle close replays if they come soon enough.  The close_lru
     * is a list of such openowners, to be reaped by the laundromat
     * thread eventually if they remain unused:
     */
    struct list_head    oo_close_lru;
    struct nfs4_ol_stateid *oo_last_closed_stid;
    time_t          oo_time; /* time of placement on so_close_lru */
#define NFS4_OO_CONFIRMED   1
#define NFS4_OO_PURGE_CLOSE 2
#define NFS4_OO_NEW         4
    unsigned char       oo_flags;
};

struct nfs4_lockowner {
    struct nfs4_stateowner  lo_owner; /* must be first element */
    struct list_head    lo_owner_ino_hash; /* hash by owner,file */
    struct list_head        lo_perstateid; /* for lockowners only */
    struct list_head    lo_list; /* for temporary uses */
};

static inline struct nfs4_openowner * openowner(struct nfs4_stateowner *so)
{
    return container_of(so, struct nfs4_openowner, oo_owner);
}

static inline struct nfs4_lockowner * lockowner(struct nfs4_stateowner *so)
{
    return container_of(so, struct nfs4_lockowner, lo_owner);
}

/* nfs4_file: a file opened by some number of (open) nfs4_stateowners. */
struct nfs4_file {
    atomic_t        fi_ref;
    struct list_head        fi_hash;    /* hash by "struct inode *" */
    struct list_head        fi_stateids;
    struct list_head    fi_delegations;
    /* One each for O_RDONLY, O_WRONLY, O_RDWR: */
    struct file *       fi_fds[3];
    /*
     * Each open or lock stateid contributes 0-4 to the counts
     * below depending on which bits are set in st_access_bitmap:
     *     1 to fi_access[O_RDONLY] if NFS4_SHARE_ACCES_READ is set
     *   + 1 to fi_access[O_WRONLY] if NFS4_SHARE_ACCESS_WRITE is set
     *   + 1 to both of the above if NFS4_SHARE_ACCESS_BOTH is set.
     */
    atomic_t        fi_access[2];
    struct file     *fi_deleg_file;
    struct file_lock    *fi_lease;
    atomic_t        fi_delegees;
    struct inode        *fi_inode;
    bool            fi_had_conflict;
};

/* XXX: for first cut may fall back on returning file that doesn't work
 * at all? */
static inline struct file *find_writeable_file(struct nfs4_file *f)
{
    if (f->fi_fds[O_WRONLY])
        return f->fi_fds[O_WRONLY];
    return f->fi_fds[O_RDWR];
}

static inline struct file *find_readable_file(struct nfs4_file *f)
{
    if (f->fi_fds[O_RDONLY])
        return f->fi_fds[O_RDONLY];
    return f->fi_fds[O_RDWR];
}

static inline struct file *find_any_file(struct nfs4_file *f)
{
    if (f->fi_fds[O_RDWR])
        return f->fi_fds[O_RDWR];
    else if (f->fi_fds[O_WRONLY])
        return f->fi_fds[O_WRONLY];
    else
        return f->fi_fds[O_RDONLY];
}

/* "ol" stands for "Open or Lock".  Better suggestions welcome. */
struct nfs4_ol_stateid {
    struct nfs4_stid    st_stid; /* must be first field */
    struct list_head              st_perfile;
    struct list_head              st_perstateowner;
    struct list_head              st_lockowners;
    struct nfs4_stateowner      * st_stateowner;
    struct nfs4_file            * st_file;
    unsigned long                 st_access_bmap;
    unsigned long                 st_deny_bmap;
    struct nfs4_ol_stateid         * st_openstp;
};

static inline struct nfs4_ol_stateid *openlockstateid(struct nfs4_stid *s)
{
    return container_of(s, struct nfs4_ol_stateid, st_stid);
}

/* flags for preprocess_seqid_op() */
#define RD_STATE            0x00000010
#define WR_STATE            0x00000020

struct nfsd4_compound_state;
struct nfsd_net;

extern __be32 nfs4_preprocess_stateid_op(struct net *net,
        struct nfsd4_compound_state *cstate,
        stateid_t *stateid, int flags, struct file **filp);
extern void nfs4_lock_state(void);
extern void nfs4_unlock_state(void);
extern int nfs4_in_grace(void);
extern void nfs4_release_reclaim(void);
extern struct nfs4_client_reclaim *nfsd4_find_reclaim_client(struct nfs4_client *crp);
extern __be32 nfs4_check_open_reclaim(clientid_t *clid, bool sessions);
extern void nfs4_free_openowner(struct nfs4_openowner *);
extern void nfs4_free_lockowner(struct nfs4_lockowner *);
extern int set_callback_cred(void);
extern void nfsd4_probe_callback(struct nfs4_client *clp);
extern void nfsd4_probe_callback_sync(struct nfs4_client *clp);
extern void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *);
extern void nfsd4_do_callback_rpc(struct work_struct *);
extern void nfsd4_cb_recall(struct nfs4_delegation *dp);
extern int nfsd4_create_callback_queue(void);
extern void nfsd4_destroy_callback_queue(void);
extern void nfsd4_shutdown_callback(struct nfs4_client *);
extern void nfs4_put_delegation(struct nfs4_delegation *dp);
extern __be32 nfs4_make_rec_clidname(char *clidname, struct xdr_netobj *clname);
extern int nfs4_client_to_reclaim(const char *name);
extern int nfs4_has_reclaimed_state(const char *name, bool use_exchange_id);
extern void release_session_client(struct nfsd4_session *);
extern void nfsd4_purge_closed_stateid(struct nfs4_stateowner *);

/* nfs4recover operations */
extern int nfsd4_client_tracking_init(struct net *net);
extern void nfsd4_client_tracking_exit(struct net *net);
extern void nfsd4_client_record_create(struct nfs4_client *clp);
extern void nfsd4_client_record_remove(struct nfs4_client *clp);
extern int nfsd4_client_record_check(struct nfs4_client *clp);
extern void nfsd4_record_grace_done(struct net *net, time_t boot_time);
#endif   /* NFSD4_STATE_H */