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/in6.h>
  16 #include <net/ipv6.h>
  17 #include <linux/fs.h>
  18 #include <linux/kref.h>
  19 #include <linux/utsname.h>
  20 #include <linux/nfsd/nfsfh.h>
  21 #include <linux/lockd/bind.h>
  22 #include <linux/lockd/xdr.h>
  23 #ifdef CONFIG_LOCKD_V4
  24 #include <linux/lockd/xdr4.h>
  25 #endif
  26 #include <linux/lockd/debug.h>
  27
  28 /*
  29  * Version string
  30  */
  31 #define LOCKD_VERSION           "0.5"
  32
  33 /*
  34  * Default timeout for RPC calls (seconds)
  35  */
  36 #define LOCKD_DFLT_TIMEO        10
  37
  38 /*
  39  * Lockd host handle (used both by the client and server personality).
  40  */
  41 struct nlm_host {
  42         struct hlist_node       h_hash;         /* doubly linked list */
  43         struct sockaddr_storage h_addr;         /* peer address */
  44         size_t                  h_addrlen;
  45         struct sockaddr_storage h_srcaddr;      /* our address (optional) */
  46         struct rpc_clnt *       h_rpcclnt;      /* RPC client to talk to peer */
  47         char *                  h_name;         /* remote hostname */
  48         u32                     h_version;      /* interface version */
  49         unsigned short          h_proto;        /* transport proto */
  50         unsigned short          h_reclaiming : 1,
  51                                 h_server     : 1, /* server side, not client side */
  52                                 h_inuse      : 1;
  53         wait_queue_head_t       h_gracewait;    /* wait while reclaiming */
  54         struct rw_semaphore     h_rwsem;        /* Reboot recovery lock */
  55         u32                     h_state;        /* pseudo-state counter */
  56         u32                     h_nsmstate;     /* true remote NSM state */
  57         u32                     h_pidcount;     /* Pseudopids */
  58         atomic_t                h_count;        /* reference count */
  59         struct mutex            h_mutex;        /* mutex for pmap binding */
  60         unsigned long           h_nextrebind;   /* next portmap call */
  61         unsigned long           h_expires;      /* eligible for GC */
  62         struct list_head        h_lockowners;   /* Lockowners for the client */
  63         spinlock_t              h_lock;
  64         struct list_head        h_granted;      /* Locks in GRANTED state */
  65         struct list_head        h_reclaim;      /* Locks in RECLAIM state */
  66         struct nsm_handle *     h_nsmhandle;    /* NSM status handle */
  67
  68         char                    h_addrbuf[48],  /* address eyecatchers */
  69                                 h_srcaddrbuf[48];
  70 };
  71
  72 struct nsm_handle {
  73         struct list_head        sm_link;
  74         atomic_t                sm_count;
  75         char *                  sm_name;
  76         struct sockaddr_storage sm_addr;
  77         size_t                  sm_addrlen;
  78         unsigned int            sm_monitored : 1,
  79                                 sm_sticky : 1;  /* don't unmonitor */
  80         char                    sm_addrbuf[48]; /* address eyecatcher */
  81 };
  82
  83 /*
  84  * Rigorous type checking on sockaddr type conversions
  85  */
  86 static inline struct sockaddr_in *nlm_addr_in(const struct nlm_host *host)
  87 {
  88         return (struct sockaddr_in *)&host->h_addr;
  89 }
  90
  91 static inline struct sockaddr *nlm_addr(const struct nlm_host *host)
  92 {
  93         return (struct sockaddr *)&host->h_addr;
  94 }
  95
  96 static inline struct sockaddr_in *nlm_srcaddr_in(const struct nlm_host *host)
  97 {
  98         return (struct sockaddr_in *)&host->h_srcaddr;
  99 }
 100
 101 static inline struct sockaddr *nlm_srcaddr(const struct nlm_host *host)
 102 {
 103         return (struct sockaddr *)&host->h_srcaddr;
 104 }
 105
 106 static inline struct sockaddr_in *nsm_addr_in(const struct nsm_handle *handle)
 107 {
 108         return (struct sockaddr_in *)&handle->sm_addr;
 109 }
 110
 111 static inline struct sockaddr *nsm_addr(const struct nsm_handle *handle)
 112 {
 113         return (struct sockaddr *)&handle->sm_addr;
 114 }
 115
 116 /*
 117  * Map an fl_owner_t into a unique 32-bit "pid"
 118  */
 119 struct nlm_lockowner {
 120         struct list_head list;
 121         atomic_t count;
 122
 123         struct nlm_host *host;
 124         fl_owner_t owner;
 125         uint32_t pid;
 126 };
 127
 128 struct nlm_wait;
 129
 130 /*
 131  * Memory chunk for NLM client RPC request.
 132  */
 133 #define NLMCLNT_OHSIZE          ((__NEW_UTS_LEN) + 10u)
 134 struct nlm_rqst {
 135         atomic_t                a_count;
 136         unsigned int            a_flags;        /* initial RPC task flags */
 137         struct nlm_host *       a_host;         /* host handle */
 138         struct nlm_args         a_args;         /* arguments */
 139         struct nlm_res          a_res;          /* result */
 140         struct nlm_block *      a_block;
 141         unsigned int            a_retries;      /* Retry count */
 142         u8                      a_owner[NLMCLNT_OHSIZE];
 143 };
 144
 145 /*
 146  * This struct describes a file held open by lockd on behalf of
 147  * an NFS client.
 148  */
 149 struct nlm_file {
 150         struct hlist_node       f_list;         /* linked list */
 151         struct nfs_fh           f_handle;       /* NFS file handle */
 152         struct file *           f_file;         /* VFS file pointer */
 153         struct nlm_share *      f_shares;       /* DOS shares */
 154         struct list_head        f_blocks;       /* blocked locks */
 155         unsigned int            f_locks;        /* guesstimate # of locks */
 156         unsigned int            f_count;        /* reference count */
 157         struct mutex            f_mutex;        /* avoid concurrent access */
 158 };
 159
 160 /*
 161  * This is a server block (i.e. a lock requested by some client which
 162  * couldn't be granted because of a conflicting lock).
 163  */
 164 #define NLM_NEVER               (~(unsigned long) 0)
 165 /* timeout on non-blocking call: */
 166 #define NLM_TIMEOUT             (7 * HZ)
 167
 168 struct nlm_block {
 169         struct kref             b_count;        /* Reference count */
 170         struct list_head        b_list;         /* linked list of all blocks */
 171         struct list_head        b_flist;        /* linked list (per file) */
 172         struct nlm_rqst *       b_call;         /* RPC args & callback info */
 173         struct svc_serv *       b_daemon;       /* NLM service */
 174         struct nlm_host *       b_host;         /* host handle for RPC clnt */
 175         unsigned long           b_when;         /* next re-xmit */
 176         unsigned int            b_id;           /* block id */
 177         unsigned char           b_granted;      /* VFS granted lock */
 178         struct nlm_file *       b_file;         /* file in question */
 179         struct cache_req *      b_cache_req;    /* deferred request handling */
 180         struct file_lock *      b_fl;           /* set for GETLK */
 181         struct cache_deferred_req * b_deferred_req;
 182         unsigned int            b_flags;        /* block flags */
 183 #define B_QUEUED                1       /* lock queued */
 184 #define B_GOT_CALLBACK          2       /* got lock or conflicting lock */
 185 #define B_TIMED_OUT             4       /* filesystem too slow to respond */
 186 };
 187
 188 /*
 189  * Global variables
 190  */
 191 extern struct rpc_program       nlm_program;
 192 extern struct svc_procedure     nlmsvc_procedures[];
 193 #ifdef CONFIG_LOCKD_V4
 194 extern struct svc_procedure     nlmsvc_procedures4[];
 195 #endif
 196 extern int                      nlmsvc_grace_period;
 197 extern unsigned long            nlmsvc_timeout;
 198 extern int                      nsm_use_hostnames;
 199
 200 /*
 201  * Lockd client functions
 202  */
 203 struct nlm_rqst * nlm_alloc_call(struct nlm_host *host);
 204 void              nlm_release_call(struct nlm_rqst *);
 205 int               nlm_async_call(struct nlm_rqst *, u32, const struct rpc_call_ops *);
 206 int               nlm_async_reply(struct nlm_rqst *, u32, const struct rpc_call_ops *);
 207 struct nlm_wait * nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *fl);
 208 void              nlmclnt_finish_block(struct nlm_wait *block);
 209 int               nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout);
 210 __be32            nlmclnt_grant(const struct sockaddr *addr,
 211                                 const struct nlm_lock *lock);
 212 void              nlmclnt_recovery(struct nlm_host *);
 213 int               nlmclnt_reclaim(struct nlm_host *, struct file_lock *);
 214 void              nlmclnt_next_cookie(struct nlm_cookie *);
 215
 216 /*
 217  * Host cache
 218  */
 219 struct nlm_host  *nlmclnt_lookup_host(const struct sockaddr *sap,
 220                                         const size_t salen,
 221                                         const unsigned short protocol,
 222                                         const u32 version,
 223                                         const char *hostname);
 224 struct nlm_host  *nlmsvc_lookup_host(const struct svc_rqst *rqstp,
 225                                         const char *hostname,
 226                                         const size_t hostname_len);
 227 struct rpc_clnt * nlm_bind_host(struct nlm_host *);
 228 void              nlm_rebind_host(struct nlm_host *);
 229 struct nlm_host * nlm_get_host(struct nlm_host *);
 230 void              nlm_release_host(struct nlm_host *);
 231 void              nlm_shutdown_hosts(void);
 232 extern void       nlm_host_rebooted(const struct sockaddr_in *, const char *,
 233                                         unsigned int, u32);
 234 void              nsm_release(struct nsm_handle *);
 235
 236
 237 /*
 238  * This is used in garbage collection and resource reclaim
 239  * A return value != 0 means destroy the lock/block/share
 240  */
 241 typedef int       (*nlm_host_match_fn_t)(void *cur, struct nlm_host *ref);
 242
 243 /*
 244  * Server-side lock handling
 245  */
 246 __be32            nlmsvc_lock(struct svc_rqst *, struct nlm_file *,
 247                               struct nlm_host *, struct nlm_lock *, int,
 248                               struct nlm_cookie *, int);
 249 __be32            nlmsvc_unlock(struct nlm_file *, struct nlm_lock *);
 250 __be32            nlmsvc_testlock(struct svc_rqst *, struct nlm_file *,
 251                         struct nlm_host *, struct nlm_lock *,
 252                         struct nlm_lock *, struct nlm_cookie *);
 253 __be32            nlmsvc_cancel_blocked(struct nlm_file *, struct nlm_lock *);
 254 unsigned long     nlmsvc_retry_blocked(void);
 255 void              nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *,
 256                                         nlm_host_match_fn_t match);
 257 void              nlmsvc_grant_reply(struct nlm_cookie *, __be32);
 258
 259 /*
 260  * File handling for the server personality
 261  */
 262 __be32            nlm_lookup_file(struct svc_rqst *, struct nlm_file **,
 263                                         struct nfs_fh *);
 264 void              nlm_release_file(struct nlm_file *);
 265 void              nlmsvc_mark_resources(void);
 266 void              nlmsvc_free_host_resources(struct nlm_host *);
 267 void              nlmsvc_invalidate_all(void);
 268
 269 /*
 270  * Cluster failover support
 271  */
 272 int           nlmsvc_unlock_all_by_sb(struct super_block *sb);
 273 int           nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr);
 274
 275 static inline struct inode *nlmsvc_file_inode(struct nlm_file *file)
 276 {
 277         return file->f_file->f_path.dentry->d_inode;
 278 }
 279
 280 static inline int __nlm_privileged_request4(const struct sockaddr *sap)
 281 {
 282         const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 283         return (sin->sin_addr.s_addr == htonl(INADDR_LOOPBACK)) &&
 284                         (ntohs(sin->sin_port) < 1024);
 285 }
 286
 287 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 288 static inline int __nlm_privileged_request6(const struct sockaddr *sap)
 289 {
 290         const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 291         return (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LOOPBACK) &&
 292                         (ntohs(sin6->sin6_port) < 1024);
 293 }
 294 #else   /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
 295 static inline int __nlm_privileged_request6(const struct sockaddr *sap)
 296 {
 297         return 0;
 298 }
 299 #endif  /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
 300
 301 /*
 302  * Ensure incoming requests are from local privileged callers.
 303  *
 304  * Return TRUE if sender is local and is connecting via a privileged port;
 305  * otherwise return FALSE.
 306  */
 307 static inline int nlm_privileged_requester(const struct svc_rqst *rqstp)
 308 {
 309         const struct sockaddr *sap = svc_addr(rqstp);
 310
 311         switch (sap->sa_family) {
 312         case AF_INET:
 313                 return __nlm_privileged_request4(sap);
 314         case AF_INET6:
 315                 return __nlm_privileged_request6(sap);
 316         default:
 317                 return 0;
 318         }
 319 }
 320
 321 static inline int __nlm_cmp_addr4(const struct sockaddr *sap1,
 322                                   const struct sockaddr *sap2)
 323 {
 324         const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sap1;
 325         const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sap2;
 326         return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
 327 }
 328
 329 static inline int __nlm_cmp_addr6(const struct sockaddr *sap1,
 330                                   const struct sockaddr *sap2)
 331 {
 332         const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sap1;
 333         const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sap2;
 334         return ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr);
 335 }
 336
 337 /*
 338  * Compare two host addresses
 339  *
 340  * Return TRUE if the addresses are the same; otherwise FALSE.
 341  */
 342 static inline int nlm_cmp_addr(const struct sockaddr *sap1,
 343                                const struct sockaddr *sap2)
 344 {
 345         if (sap1->sa_family == sap2->sa_family) {
 346                 switch (sap1->sa_family) {
 347                 case AF_INET:
 348                         return __nlm_cmp_addr4(sap1, sap2);
 349                 case AF_INET6:
 350                         return __nlm_cmp_addr6(sap1, sap2);
 351                 }
 352         }
 353         return 0;
 354 }
 355
 356 /*
 357  * Compare two NLM locks.
 358  * When the second lock is of type F_UNLCK, this acts like a wildcard.
 359  */
 360 static inline int nlm_compare_locks(const struct file_lock *fl1,
 361                                     const struct file_lock *fl2)
 362 {
 363         return  fl1->fl_pid   == fl2->fl_pid
 364              && fl1->fl_owner == fl2->fl_owner
 365              && fl1->fl_start == fl2->fl_start
 366              && fl1->fl_end   == fl2->fl_end
 367              &&(fl1->fl_type  == fl2->fl_type || fl2->fl_type == F_UNLCK);
 368 }
 369
 370 extern struct lock_manager_operations nlmsvc_lock_operations;
 371
 372 #endif /* __KERNEL__ */
 373
 374 #endif /* LINUX_LOCKD_LOCKD_H */