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/config.h>
  15 #include <linux/in.h>
  16 #include <linux/fs.h>
  17 #include <linux/kref.h>
  18 #include <linux/utsname.h>
  19 #include <linux/nfsd/nfsfh.h>
  20 #include <linux/lockd/bind.h>
  21 #include <linux/lockd/xdr.h>
  22 #ifdef CONFIG_LOCKD_V4
  23 #include <linux/lockd/xdr4.h>
  24 #endif
  25 #include <linux/lockd/debug.h>
  26
  27 /*
  28  * Version string
  29  */
  30 #define LOCKD_VERSION           "0.5"
  31
  32 /*
  33  * Default timeout for RPC calls (seconds)
  34  */
  35 #define LOCKD_DFLT_TIMEO        10
  36
  37 /*
  38  * Lockd host handle (used both by the client and server personality).
  39  */
  40 struct nlm_host {
  41         struct nlm_host *       h_next;         /* linked list (hash table) */
  42         struct sockaddr_in      h_addr;         /* peer address */
  43         struct rpc_clnt *       h_rpcclnt;      /* RPC client to talk to peer */
  44         char                    h_name[20];     /* 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                                 h_killed     : 1,
  51                                 h_monitored  : 1;
  52         wait_queue_head_t       h_gracewait;    /* wait while reclaiming */
  53         u32                     h_state;        /* pseudo-state counter */
  54         u32                     h_nsmstate;     /* true remote NSM state */
  55         u32                     h_pidcount;     /* Pseudopids */
  56         atomic_t                h_count;        /* reference count */
  57         struct semaphore        h_sema;         /* mutex for pmap binding */
  58         unsigned long           h_nextrebind;   /* next portmap call */
  59         unsigned long           h_expires;      /* eligible for GC */
  60         struct list_head        h_lockowners;   /* Lockowners for the client */
  61         spinlock_t              h_lock;
  62         struct list_head        h_granted;      /* Locks in GRANTED state */
  63         struct list_head        h_reclaim;      /* Locks in RECLAIM state */
  64 };
  65
  66 /*
  67  * Map an fl_owner_t into a unique 32-bit "pid"
  68  */
  69 struct nlm_lockowner {
  70         struct list_head list;
  71         atomic_t count;
  72
  73         struct nlm_host *host;
  74         fl_owner_t owner;
  75         uint32_t pid;
  76 };
  77
  78 struct nlm_wait;
  79
  80 /*
  81  * Memory chunk for NLM client RPC request.
  82  */
  83 #define NLMCLNT_OHSIZE          (sizeof(system_utsname.nodename)+10)
  84 struct nlm_rqst {
  85         unsigned int            a_flags;        /* initial RPC task flags */
  86         struct nlm_host *       a_host;         /* host handle */
  87         struct nlm_args         a_args;         /* arguments */
  88         struct nlm_res          a_res;          /* result */
  89         struct nlm_block *      a_block;
  90         unsigned int            a_retries;      /* Retry count */
  91         u8                      a_owner[NLMCLNT_OHSIZE];
  92 };
  93
  94 /*
  95  * This struct describes a file held open by lockd on behalf of
  96  * an NFS client.
  97  */
  98 struct nlm_file {
  99         struct nlm_file *       f_next;         /* linked list */
 100         struct nfs_fh           f_handle;       /* NFS file handle */
 101         struct file *           f_file;         /* VFS file pointer */
 102         struct nlm_share *      f_shares;       /* DOS shares */
 103         struct nlm_block *      f_blocks;       /* blocked locks */
 104         unsigned int            f_locks;        /* guesstimate # of locks */
 105         unsigned int            f_count;        /* reference count */
 106         struct semaphore        f_sema;         /* avoid concurrent access */
 107         int                     f_hash;         /* hash of f_handle */
 108 };
 109
 110 /*
 111  * This is a server block (i.e. a lock requested by some client which
 112  * couldn't be granted because of a conflicting lock).
 113  */
 114 #define NLM_NEVER               (~(unsigned long) 0)
 115 struct nlm_block {
 116         struct kref             b_count;        /* Reference count */
 117         struct nlm_block *      b_next;         /* linked list (all blocks) */
 118         struct nlm_block *      b_fnext;        /* linked list (per file) */
 119         struct nlm_rqst *       b_call;         /* RPC args & callback info */
 120         struct svc_serv *       b_daemon;       /* NLM service */
 121         struct nlm_host *       b_host;         /* host handle for RPC clnt */
 122         unsigned long           b_when;         /* next re-xmit */
 123         unsigned int            b_id;           /* block id */
 124         unsigned char           b_queued;       /* re-queued */
 125         unsigned char           b_granted;      /* VFS granted lock */
 126         unsigned char           b_done;         /* callback complete */
 127         struct nlm_file *       b_file;         /* file in question */
 128 };
 129
 130 /*
 131  * Valid actions for nlmsvc_traverse_files
 132  */
 133 #define NLM_ACT_CHECK           0               /* check for locks */
 134 #define NLM_ACT_MARK            1               /* mark & sweep */
 135 #define NLM_ACT_UNLOCK          2               /* release all locks */
 136
 137 /*
 138  * Global variables
 139  */
 140 extern struct rpc_program       nlm_program;
 141 extern struct svc_procedure     nlmsvc_procedures[];
 142 #ifdef CONFIG_LOCKD_V4
 143 extern struct svc_procedure     nlmsvc_procedures4[];
 144 #endif
 145 extern int                      nlmsvc_grace_period;
 146 extern unsigned long            nlmsvc_timeout;
 147
 148 /*
 149  * Lockd client functions
 150  */
 151 struct nlm_rqst * nlm_alloc_call(struct nlm_host *host);
 152 void              nlm_release_call(struct nlm_rqst *);
 153 int               nlm_async_call(struct nlm_rqst *, u32, const struct rpc_call_ops *);
 154 int               nlm_async_reply(struct nlm_rqst *, u32, const struct rpc_call_ops *);
 155 struct nlm_wait * nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *fl);
 156 void              nlmclnt_finish_block(struct nlm_wait *block);
 157 int               nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout);
 158 u32               nlmclnt_grant(const struct sockaddr_in *addr, const struct nlm_lock *);
 159 void              nlmclnt_recovery(struct nlm_host *, u32);
 160 int               nlmclnt_reclaim(struct nlm_host *, struct file_lock *);
 161
 162 /*
 163  * Host cache
 164  */
 165 struct nlm_host * nlmclnt_lookup_host(struct sockaddr_in *, int, int);
 166 struct nlm_host * nlmsvc_lookup_host(struct svc_rqst *);
 167 struct nlm_host * nlm_lookup_host(int server, struct sockaddr_in *, int, int);
 168 struct rpc_clnt * nlm_bind_host(struct nlm_host *);
 169 void              nlm_rebind_host(struct nlm_host *);
 170 struct nlm_host * nlm_get_host(struct nlm_host *);
 171 void              nlm_release_host(struct nlm_host *);
 172 void              nlm_shutdown_hosts(void);
 173 extern struct nlm_host *nlm_find_client(void);
 174
 175
 176 /*
 177  * Server-side lock handling
 178  */
 179 u32               nlmsvc_lock(struct svc_rqst *, struct nlm_file *,
 180                                         struct nlm_lock *, int, struct nlm_cookie *);
 181 u32               nlmsvc_unlock(struct nlm_file *, struct nlm_lock *);
 182 u32               nlmsvc_testlock(struct nlm_file *, struct nlm_lock *,
 183                                         struct nlm_lock *);
 184 u32               nlmsvc_cancel_blocked(struct nlm_file *, struct nlm_lock *);
 185 unsigned long     nlmsvc_retry_blocked(void);
 186 void              nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *,
 187                                         int action);
 188 void      nlmsvc_grant_reply(struct svc_rqst *, struct nlm_cookie *, u32);
 189
 190 /*
 191  * File handling for the server personality
 192  */
 193 u32               nlm_lookup_file(struct svc_rqst *, struct nlm_file **,
 194                                         struct nfs_fh *);
 195 void              nlm_release_file(struct nlm_file *);
 196 void              nlmsvc_mark_resources(void);
 197 void              nlmsvc_free_host_resources(struct nlm_host *);
 198 void              nlmsvc_invalidate_all(void);
 199
 200 static __inline__ struct inode *
 201 nlmsvc_file_inode(struct nlm_file *file)
 202 {
 203         return file->f_file->f_dentry->d_inode;
 204 }
 205
 206 /*
 207  * Compare two host addresses (needs modifying for ipv6)
 208  */
 209 static __inline__ int
 210 nlm_cmp_addr(const struct sockaddr_in *sin1, const struct sockaddr_in *sin2)
 211 {
 212         return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
 213 }
 214
 215 /*
 216  * Compare two NLM locks.
 217  * When the second lock is of type F_UNLCK, this acts like a wildcard.
 218  */
 219 static __inline__ int
 220 nlm_compare_locks(const struct file_lock *fl1, const struct file_lock *fl2)
 221 {
 222         return  fl1->fl_pid   == fl2->fl_pid
 223              && fl1->fl_start == fl2->fl_start
 224              && fl1->fl_end   == fl2->fl_end
 225              &&(fl1->fl_type  == fl2->fl_type || fl2->fl_type == F_UNLCK);
 226 }
 227
 228 extern struct lock_manager_operations nlmsvc_lock_operations;
 229
 230 #endif /* __KERNEL__ */
 231
 232 #endif /* LINUX_LOCKD_LOCKD_H */