LXR linux/include/linux/lockd/lockd.h

   1/*
   2 * linux/include/linux/lockd/lockd.h
   3 *
   4 * General-purpose lockd include file.
   5 *
   6 * Copyright (C) 1996 Olaf Kirch <okir@monad.swb.de>
   7 */
   8
   9#ifndef LINUX_LOCKD_LOCKD_H
  10#define LINUX_LOCKD_LOCKD_H
  11
  12#ifdef __KERNEL__
  13
  14#include <linux/in.h>
  15#include <linux/fs.h>
  16#include <linux/kref.h>
  17#include <linux/utsname.h>
  18#include <linux/nfsd/nfsfh.h>
  19#include <linux/lockd/bind.h>
  20#include <linux/lockd/xdr.h>
  21#ifdef CONFIG_LOCKD_V4
  22#include <linux/lockd/xdr4.h>
  23#endif
  24#include <linux/lockd/debug.h>
  25
  26/*
  27 * Version string
  28 */
  29#define LOCKD_VERSION           "0.5"
  30
  31/*
  32 * Default timeout for RPC calls (seconds)
  33 */
  34#define LOCKD_DFLT_TIMEO        10
  35
  36/*
  37 * Lockd host handle (used both by the client and server personality).
  38 */
  39struct nlm_host {
  40        struct hlist_node       h_hash;         /* doubly linked list */
  41        struct sockaddr_in      h_addr;         /* peer address */
  42        struct sockaddr_in      h_saddr;        /* our address (optional) */
  43        struct rpc_clnt *       h_rpcclnt;      /* RPC client to talk to peer */
  44        char *                  h_name;         /* remote hostname */
  45        u32                     h_version;      /* interface version */
  46        unsigned short          h_proto;        /* transport proto */
  47        unsigned short          h_reclaiming : 1,
  48                                h_server     : 1, /* server side, not client side */
  49                                h_inuse      : 1;
  50        wait_queue_head_t       h_gracewait;    /* wait while reclaiming */
  51        struct rw_semaphore     h_rwsem;        /* Reboot recovery lock */
  52        u32                     h_state;        /* pseudo-state counter */
  53        u32                     h_nsmstate;     /* true remote NSM state */
  54        u32                     h_pidcount;     /* Pseudopids */
  55        atomic_t                h_count;        /* reference count */
  56        struct mutex            h_mutex;        /* mutex for pmap binding */
  57        unsigned long           h_nextrebind;   /* next portmap call */
  58        unsigned long           h_expires;      /* eligible for GC */
  59        struct list_head        h_lockowners;   /* Lockowners for the client */
  60        spinlock_t              h_lock;
  61        struct list_head        h_granted;      /* Locks in GRANTED state */
  62        struct list_head        h_reclaim;      /* Locks in RECLAIM state */
  63        struct nsm_handle *     h_nsmhandle;    /* NSM status handle */
  64};
  65
  66struct nsm_handle {
  67        struct list_head        sm_link;
  68        atomic_t                sm_count;
  69        char *                  sm_name;
  70        struct sockaddr_in      sm_addr;
  71        unsigned int            sm_monitored : 1,
  72                                sm_sticky : 1;  /* don't unmonitor */
  73};
  74
  75/*
  76 * Map an fl_owner_t into a unique 32-bit "pid"
  77 */
  78struct nlm_lockowner {
  79        struct list_head list;
  80        atomic_t count;
  81
  82        struct nlm_host *host;
  83        fl_owner_t owner;
  84        uint32_t pid;
  85};
  86
  87struct nlm_wait;
  88
  89/*
  90 * Memory chunk for NLM client RPC request.
  91 */
  92#define NLMCLNT_OHSIZE          ((__NEW_UTS_LEN) + 10u)
  93struct nlm_rqst {
  94        unsigned int            a_flags;        /* initial RPC task flags */
  95        struct nlm_host *       a_host;         /* host handle */
  96        struct nlm_args         a_args;         /* arguments */
  97        struct nlm_res          a_res;          /* result */
  98        struct nlm_block *      a_block;
  99        unsigned int            a_retries;      /* Retry count */
 100        u8                      a_owner[NLMCLNT_OHSIZE];
 101};
 102
 103/*
 104 * This struct describes a file held open by lockd on behalf of
 105 * an NFS client.
 106 */
 107struct nlm_file {
 108        struct hlist_node       f_list;         /* linked list */
 109        struct nfs_fh           f_handle;       /* NFS file handle */
 110        struct file *           f_file;         /* VFS file pointer */
 111        struct nlm_share *      f_shares;       /* DOS shares */
 112        struct list_head        f_blocks;       /* blocked locks */
 113        unsigned int            f_locks;        /* guesstimate # of locks */
 114        unsigned int            f_count;        /* reference count */
 115        struct mutex            f_mutex;        /* avoid concurrent access */
 116};
 117
 118/*
 119 * This is a server block (i.e. a lock requested by some client which
 120 * couldn't be granted because of a conflicting lock).
 121 */
 122#define NLM_NEVER               (~(unsigned long) 0)
 123/* timeout on non-blocking call: */
 124#define NLM_TIMEOUT             (7 * HZ)
 125
 126struct nlm_block {
 127        struct kref             b_count;        /* Reference count */
 128        struct list_head        b_list;         /* linked list of all blocks */
 129        struct list_head        b_flist;        /* linked list (per file) */
 130        struct nlm_rqst *       b_call;         /* RPC args & callback info */
 131        struct svc_serv *       b_daemon;       /* NLM service */
 132        struct nlm_host *       b_host;         /* host handle for RPC clnt */
 133        unsigned long           b_when;         /* next re-xmit */
 134        unsigned int            b_id;           /* block id */
 135        unsigned char           b_granted;      /* VFS granted lock */
 136        struct nlm_file *       b_file;         /* file in question */
 137        struct cache_req *      b_cache_req;    /* deferred request handling */
 138        struct file_lock *      b_fl;           /* set for GETLK */
 139        struct cache_deferred_req * b_deferred_req;
 140        unsigned int            b_flags;        /* block flags */
 141#define B_QUEUED                1       /* lock queued */
 142#define B_GOT_CALLBACK          2       /* got lock or conflicting lock */
 143#define B_TIMED_OUT             4       /* filesystem too slow to respond */
 144};
 145
 146/*
 147 * Global variables
 148 */
 149extern struct rpc_program       nlm_program;
 150extern struct svc_procedure     nlmsvc_procedures[];
 151#ifdef CONFIG_LOCKD_V4
 152extern struct svc_procedure     nlmsvc_procedures4[];
 153#endif
 154extern int                      nlmsvc_grace_period;
 155extern unsigned long            nlmsvc_timeout;
 156extern int                      nsm_use_hostnames;
 157
 158/*
 159 * Lockd client functions
 160 */
 161struct nlm_rqst * nlm_alloc_call(struct nlm_host *host);
 162void              nlm_release_call(struct nlm_rqst *);
 163int               nlm_async_call(struct nlm_rqst *, u32, const struct rpc_call_ops *);
 164int               nlm_async_reply(struct nlm_rqst *, u32, const struct rpc_call_ops *);
 165struct nlm_wait * nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *fl);
 166void              nlmclnt_finish_block(struct nlm_wait *block);
 167int               nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout);
 168__be32            nlmclnt_grant(const struct sockaddr_in *addr, const struct nlm_lock *);
 169void              nlmclnt_recovery(struct nlm_host *);
 170int               nlmclnt_reclaim(struct nlm_host *, struct file_lock *);
 171void              nlmclnt_next_cookie(struct nlm_cookie *);
 172
 173/*
 174 * Host cache
 175 */
 176struct nlm_host * nlmclnt_lookup_host(const struct sockaddr_in *, int, int, const char *, int);
 177struct nlm_host * nlmsvc_lookup_host(struct svc_rqst *, const char *, int);
 178struct rpc_clnt * nlm_bind_host(struct nlm_host *);
 179void              nlm_rebind_host(struct nlm_host *);
 180struct nlm_host * nlm_get_host(struct nlm_host *);
 181void              nlm_release_host(struct nlm_host *);
 182void              nlm_shutdown_hosts(void);
 183extern void       nlm_host_rebooted(const struct sockaddr_in *, const char *, int, u32);
 184void              nsm_release(struct nsm_handle *);
 185
 186
 187/*
 188 * This is used in garbage collection and resource reclaim
 189 * A return value != 0 means destroy the lock/block/share
 190 */
 191typedef int       (*nlm_host_match_fn_t)(struct nlm_host *cur, struct nlm_host *ref);
 192
 193/*
 194 * Server-side lock handling
 195 */
 196__be32            nlmsvc_lock(struct svc_rqst *, struct nlm_file *,
 197                                        struct nlm_lock *, int, struct nlm_cookie *);
 198__be32            nlmsvc_unlock(struct nlm_file *, struct nlm_lock *);
 199__be32            nlmsvc_testlock(struct svc_rqst *, struct nlm_file *,
 200                        struct nlm_lock *, struct nlm_lock *, struct nlm_cookie *);
 201__be32            nlmsvc_cancel_blocked(struct nlm_file *, struct nlm_lock *);
 202unsigned long     nlmsvc_retry_blocked(void);
 203void              nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *,
 204                                        nlm_host_match_fn_t match);
 205void              nlmsvc_grant_reply(struct nlm_cookie *, __be32);
 206
 207/*
 208 * File handling for the server personality
 209 */
 210__be32            nlm_lookup_file(struct svc_rqst *, struct nlm_file **,
 211                                        struct nfs_fh *);
 212void              nlm_release_file(struct nlm_file *);
 213void              nlmsvc_mark_resources(void);
 214void              nlmsvc_free_host_resources(struct nlm_host *);
 215void              nlmsvc_invalidate_all(void);
 216
 217static __inline__ struct inode *
 218nlmsvc_file_inode(struct nlm_file *file)
 219{
 220        return file->f_file->f_path.dentry->d_inode;
 221}
 222
 223/*
 224 * Compare two host addresses (needs modifying for ipv6)
 225 */
 226static __inline__ int
 227nlm_cmp_addr(const struct sockaddr_in *sin1, const struct sockaddr_in *sin2)
 228{
 229        return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
 230}
 231
 232/*
 233 * Compare two NLM locks.
 234 * When the second lock is of type F_UNLCK, this acts like a wildcard.
 235 */
 236static __inline__ int
 237nlm_compare_locks(const struct file_lock *fl1, const struct file_lock *fl2)
 238{
 239        return  fl1->fl_pid   == fl2->fl_pid
 240             && fl1->fl_owner == fl2->fl_owner
 241             && fl1->fl_start == fl2->fl_start
 242             && fl1->fl_end   == fl2->fl_end
 243             &&(fl1->fl_type  == fl2->fl_type || fl2->fl_type == F_UNLCK);
 244}
 245
 246extern struct lock_manager_operations nlmsvc_lock_operations;
 247
 248#endif /* __KERNEL__ */
 249
 250#endif /* LINUX_LOCKD_LOCKD_H */
 251