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 hlist_node       h_hash;         /* doubly linked list */
  41         struct sockaddr_in      h_addr;         /* peer address */
  42         struct rpc_clnt *       h_rpcclnt;      /* RPC client to talk to peer */
  43         char *                  h_name;         /* 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         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
  66 struct 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  */
  78 struct 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
  87 struct nlm_wait;
  88
  89 /*
  90  * Memory chunk for NLM client RPC request.
  91  */
  92 #define NLMCLNT_OHSIZE          (sizeof(utsname()->nodename)+10)
  93 struct 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  */
 107 struct 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 semaphore        f_sema;         /* 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 struct nlm_block {
 124         struct kref             b_count;        /* Reference count */
 125         struct list_head        b_list;         /* linked list of all blocks */
 126         struct list_head        b_flist;        /* linked list (per file) */
 127         struct nlm_rqst *       b_call;         /* RPC args & callback info */
 128         struct svc_serv *       b_daemon;       /* NLM service */
 129         struct nlm_host *       b_host;         /* host handle for RPC clnt */
 130         unsigned long           b_when;         /* next re-xmit */
 131         unsigned int            b_id;           /* block id */
 132         unsigned char           b_granted;      /* VFS granted lock */
 133         struct nlm_file *       b_file;         /* file in question */
 134 };
 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 *);
 159 int               nlmclnt_reclaim(struct nlm_host *, struct file_lock *);
 160
 161 /*
 162  * Host cache
 163  */
 164 struct nlm_host * nlmclnt_lookup_host(const struct sockaddr_in *, int, int, const char *, int);
 165 struct nlm_host * nlmsvc_lookup_host(struct svc_rqst *, const char *, int);
 166 struct nlm_host * nlm_lookup_host(int server, const struct sockaddr_in *, int, int, const char *, 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 extern void       nlm_host_rebooted(const struct sockaddr_in *, const char *, int, u32);
 174 struct nsm_handle *nsm_find(const struct sockaddr_in *, const char *, int);
 175 void              nsm_release(struct nsm_handle *);
 176
 177
 178 /*
 179  * This is used in garbage collection and resource reclaim
 180  * A return value != 0 means destroy the lock/block/share
 181  */
 182 typedef int       (*nlm_host_match_fn_t)(struct nlm_host *cur, struct nlm_host *ref);
 183
 184 /*
 185  * Server-side lock handling
 186  */
 187 u32               nlmsvc_lock(struct svc_rqst *, struct nlm_file *,
 188                                         struct nlm_lock *, int, struct nlm_cookie *);
 189 u32               nlmsvc_unlock(struct nlm_file *, struct nlm_lock *);
 190 u32               nlmsvc_testlock(struct nlm_file *, struct nlm_lock *,
 191                                         struct nlm_lock *);
 192 u32               nlmsvc_cancel_blocked(struct nlm_file *, struct nlm_lock *);
 193 unsigned long     nlmsvc_retry_blocked(void);
 194 void              nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *,
 195                                         nlm_host_match_fn_t match);
 196 void      nlmsvc_grant_reply(struct svc_rqst *, struct nlm_cookie *, u32);
 197
 198 /*
 199  * File handling for the server personality
 200  */
 201 u32               nlm_lookup_file(struct svc_rqst *, struct nlm_file **,
 202                                         struct nfs_fh *);
 203 void              nlm_release_file(struct nlm_file *);
 204 void              nlmsvc_mark_resources(void);
 205 void              nlmsvc_free_host_resources(struct nlm_host *);
 206 void              nlmsvc_invalidate_all(void);
 207
 208 static __inline__ struct inode *
 209 nlmsvc_file_inode(struct nlm_file *file)
 210 {
 211         return file->f_file->f_dentry->d_inode;
 212 }
 213
 214 /*
 215  * Compare two host addresses (needs modifying for ipv6)
 216  */
 217 static __inline__ int
 218 nlm_cmp_addr(const struct sockaddr_in *sin1, const struct sockaddr_in *sin2)
 219 {
 220         return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
 221 }
 222
 223 /*
 224  * Compare two NLM locks.
 225  * When the second lock is of type F_UNLCK, this acts like a wildcard.
 226  */
 227 static __inline__ int
 228 nlm_compare_locks(const struct file_lock *fl1, const struct file_lock *fl2)
 229 {
 230         return  fl1->fl_pid   == fl2->fl_pid
 231              && fl1->fl_owner == fl2->fl_owner
 232              && fl1->fl_start == fl2->fl_start
 233              && fl1->fl_end   == fl2->fl_end
 234              &&(fl1->fl_type  == fl2->fl_type || fl2->fl_type == F_UNLCK);
 235 }
 236
 237 extern struct lock_manager_operations nlmsvc_lock_operations;
 238
 239 #endif /* __KERNEL__ */
 240
 241 #endif /* LINUX_LOCKD_LOCKD_H */