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         struct rw_semaphore     h_rwsem;        /* Reboot recovery lock */
  54         u32                     h_state;        /* pseudo-state counter */
  55         u32                     h_nsmstate;     /* true remote NSM state */
  56         u32                     h_pidcount;     /* Pseudopids */
  57         atomic_t                h_count;        /* reference count */
  58         struct mutex            h_mutex;        /* mutex for pmap binding */
  59         unsigned long           h_nextrebind;   /* next portmap call */
  60         unsigned long           h_expires;      /* eligible for GC */
  61         struct list_head        h_lockowners;   /* Lockowners for the client */
  62         spinlock_t              h_lock;
  63         struct list_head        h_granted;      /* Locks in GRANTED state */
  64         struct list_head        h_reclaim;      /* Locks in RECLAIM state */
  65 };
  66
  67 /*
  68  * Map an fl_owner_t into a unique 32-bit "pid"
  69  */
  70 struct nlm_lockowner {
  71         struct list_head list;
  72         atomic_t count;
  73
  74         struct nlm_host *host;
  75         fl_owner_t owner;
  76         uint32_t pid;
  77 };
  78
  79 struct nlm_wait;
  80
  81 /*
  82  * Memory chunk for NLM client RPC request.
  83  */
  84 #define NLMCLNT_OHSIZE          (sizeof(system_utsname.nodename)+10)
  85 struct nlm_rqst {
  86         unsigned int            a_flags;        /* initial RPC task flags */
  87         struct nlm_host *       a_host;         /* host handle */
  88         struct nlm_args         a_args;         /* arguments */
  89         struct nlm_res          a_res;          /* result */
  90         struct nlm_block *      a_block;
  91         unsigned int            a_retries;      /* Retry count */
  92         u8                      a_owner[NLMCLNT_OHSIZE];
  93 };
  94
  95 /*
  96  * This struct describes a file held open by lockd on behalf of
  97  * an NFS client.
  98  */
  99 struct nlm_file {
 100         struct nlm_file *       f_next;         /* linked list */
 101         struct nfs_fh           f_handle;       /* NFS file handle */
 102         struct file *           f_file;         /* VFS file pointer */
 103         struct nlm_share *      f_shares;       /* DOS shares */
 104         struct nlm_block *      f_blocks;       /* blocked locks */
 105         unsigned int            f_locks;        /* guesstimate # of locks */
 106         unsigned int            f_count;        /* reference count */
 107         struct semaphore        f_sema;         /* avoid concurrent access */
 108         int                     f_hash;         /* hash of f_handle */
 109 };
 110
 111 /*
 112  * This is a server block (i.e. a lock requested by some client which
 113  * couldn't be granted because of a conflicting lock).
 114  */
 115 #define NLM_NEVER               (~(unsigned long) 0)
 116 struct nlm_block {
 117         struct kref             b_count;        /* Reference count */
 118         struct nlm_block *      b_next;         /* linked list (all blocks) */
 119         struct nlm_block *      b_fnext;        /* linked list (per file) */
 120         struct nlm_rqst *       b_call;         /* RPC args & callback info */
 121         struct svc_serv *       b_daemon;       /* NLM service */
 122         struct nlm_host *       b_host;         /* host handle for RPC clnt */
 123         unsigned long           b_when;         /* next re-xmit */
 124         unsigned int            b_id;           /* block id */
 125         unsigned char           b_queued;       /* re-queued */
 126         unsigned char           b_granted;      /* VFS granted lock */
 127         unsigned char           b_done;         /* callback complete */
 128         struct nlm_file *       b_file;         /* file in question */
 129 };
 130
 131 /*
 132  * Valid actions for nlmsvc_traverse_files
 133  */
 134 #define NLM_ACT_CHECK           0               /* check for locks */
 135 #define NLM_ACT_MARK            1               /* mark & sweep */
 136 #define NLM_ACT_UNLOCK          2               /* release all locks */
 137
 138 /*
 139  * Global variables
 140  */
 141 extern struct rpc_program       nlm_program;
 142 extern struct svc_procedure     nlmsvc_procedures[];
 143 #ifdef CONFIG_LOCKD_V4
 144 extern struct svc_procedure     nlmsvc_procedures4[];
 145 #endif
 146 extern int                      nlmsvc_grace_period;
 147 extern unsigned long            nlmsvc_timeout;
 148
 149 /*
 150  * Lockd client functions
 151  */
 152 struct nlm_rqst * nlm_alloc_call(struct nlm_host *host);
 153 void              nlm_release_call(struct nlm_rqst *);
 154 int               nlm_async_call(struct nlm_rqst *, u32, const struct rpc_call_ops *);
 155 int               nlm_async_reply(struct nlm_rqst *, u32, const struct rpc_call_ops *);
 156 struct nlm_wait * nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *fl);
 157 void              nlmclnt_finish_block(struct nlm_wait *block);
 158 int               nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout);
 159 u32               nlmclnt_grant(const struct sockaddr_in *addr, const struct nlm_lock *);
 160 void              nlmclnt_recovery(struct nlm_host *, u32);
 161 int               nlmclnt_reclaim(struct nlm_host *, struct file_lock *);
 162
 163 /*
 164  * Host cache
 165  */
 166 struct nlm_host * nlmclnt_lookup_host(struct sockaddr_in *, int, int);
 167 struct nlm_host * nlmsvc_lookup_host(struct svc_rqst *);
 168 struct nlm_host * nlm_lookup_host(int server, struct sockaddr_in *, int, int);
 169 struct rpc_clnt * nlm_bind_host(struct nlm_host *);
 170 void              nlm_rebind_host(struct nlm_host *);
 171 struct nlm_host * nlm_get_host(struct nlm_host *);
 172 void              nlm_release_host(struct nlm_host *);
 173 void              nlm_shutdown_hosts(void);
 174 extern struct nlm_host *nlm_find_client(void);
 175
 176
 177 /*
 178  * Server-side lock handling
 179  */
 180 u32               nlmsvc_lock(struct svc_rqst *, struct nlm_file *,
 181                                         struct nlm_lock *, int, struct nlm_cookie *);
 182 u32               nlmsvc_unlock(struct nlm_file *, struct nlm_lock *);
 183 u32               nlmsvc_testlock(struct nlm_file *, struct nlm_lock *,
 184                                         struct nlm_lock *);
 185 u32               nlmsvc_cancel_blocked(struct nlm_file *, struct nlm_lock *);
 186 unsigned long     nlmsvc_retry_blocked(void);
 187 void              nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *,
 188                                         int action);
 189 void      nlmsvc_grant_reply(struct svc_rqst *, struct nlm_cookie *, u32);
 190
 191 /*
 192  * File handling for the server personality
 193  */
 194 u32               nlm_lookup_file(struct svc_rqst *, struct nlm_file **,
 195                                         struct nfs_fh *);
 196 void              nlm_release_file(struct nlm_file *);
 197 void              nlmsvc_mark_resources(void);
 198 void              nlmsvc_free_host_resources(struct nlm_host *);
 199 void              nlmsvc_invalidate_all(void);
 200
 201 static __inline__ struct inode *
 202 nlmsvc_file_inode(struct nlm_file *file)
 203 {
 204         return file->f_file->f_dentry->d_inode;
 205 }
 206
 207 /*
 208  * Compare two host addresses (needs modifying for ipv6)
 209  */
 210 static __inline__ int
 211 nlm_cmp_addr(const struct sockaddr_in *sin1, const struct sockaddr_in *sin2)
 212 {
 213         return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
 214 }
 215
 216 /*
 217  * Compare two NLM locks.
 218  * When the second lock is of type F_UNLCK, this acts like a wildcard.
 219  */
 220 static __inline__ int
 221 nlm_compare_locks(const struct file_lock *fl1, const struct file_lock *fl2)
 222 {
 223         return  fl1->fl_pid   == fl2->fl_pid
 224              && fl1->fl_owner == fl2->fl_owner
 225              && fl1->fl_start == fl2->fl_start
 226              && fl1->fl_end   == fl2->fl_end
 227              &&(fl1->fl_type  == fl2->fl_type || fl2->fl_type == F_UNLCK);
 228 }
 229
 230 extern struct lock_manager_operations nlmsvc_lock_operations;
 231
 232 #endif /* __KERNEL__ */
 233
 234 #endif /* LINUX_LOCKD_LOCKD_H */