fs/nfsd/lockd.c

   1 /*
   2  * linux/fs/nfsd/lockd.c
   3  *
   4  * This file contains all the stubs needed when communicating with lockd.
   5  * This level of indirection is necessary so we can run nfsd+lockd without
   6  * requiring the nfs client to be compiled in/loaded, and vice versa.
   7  *
   8  * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
   9  */
  10
  11 #include <linux/types.h>
  12 #include <linux/fs.h>
  13 #include <linux/mount.h>
  14 #include <linux/sunrpc/clnt.h>
  15 #include <linux/sunrpc/svc.h>
  16 #include <linux/nfsd/nfsd.h>
  17 #include <linux/lockd/bind.h>
  18
  19 #define NFSDDBG_FACILITY                NFSDDBG_LOCKD
  20
  21 /*
  22  * Note: we hold the dentry use count while the file is open.
  23  */
  24 static u32
  25 nlm_fopen(struct svc_rqst *rqstp, struct nfs_fh *f, struct file *filp)
  26 {
  27         u32             nfserr;
  28         struct svc_fh   fh;
  29
  30         /* must initialize before using! but maxsize doesn't matter */
  31         fh_init(&fh,0);
  32         fh.fh_handle.fh_size = f->size;
  33         memcpy((char*)&fh.fh_handle.fh_base, f->data, f->size);
  34         fh.fh_export = NULL;
  35
  36         exp_readlock();
  37         nfserr = nfsd_open(rqstp, &fh, S_IFREG, MAY_LOCK, filp);
  38         if (!nfserr) {
  39                 dget(filp->f_dentry);
  40                 mntget(filp->f_vfsmnt);
  41         }
  42         fh_put(&fh);
  43         rqstp->rq_client = NULL;
  44         exp_readunlock();
  45         /* nlm and nfsd don't share error codes.
  46          * we invent: 0 = no error
  47          *            1 = stale file handle
  48          *            2 = other error
  49          */
  50         switch (nfserr) {
  51         case nfs_ok:
  52                 return 0;
  53         case nfserr_stale:
  54                 return 1;
  55         default:
  56                 return 2;
  57         }
  58 }
  59
  60 static void
  61 nlm_fclose(struct file *filp)
  62 {
  63         nfsd_close(filp);
  64         dput(filp->f_dentry);
  65         mntput(filp->f_vfsmnt);
  66 }
  67
  68 struct nlmsvc_binding           nfsd_nlm_ops = {
  69         .fopen          = nlm_fopen,            /* open file for locking */
  70         .fclose         = nlm_fclose,           /* close file */
  71 };
  72
  73 void
  74 nfsd_lockd_init(void)
  75 {
  76         dprintk("nfsd: initializing lockd\n");
  77         nlmsvc_ops = &nfsd_nlm_ops;
  78 }
  79
  80 void
  81 nfsd_lockd_shutdown(void)
  82 {
  83         nlmsvc_ops = NULL;
  84 }