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