fs/nfs/nfs42proc.c

   1 /*
   2  * Copyright (c) 2014 Anna Schumaker <Anna.Schumaker@Netapp.com>
   3  */
   4 #include <linux/fs.h>
   5 #include <linux/sunrpc/sched.h>
   6 #include <linux/nfs.h>
   7 #include <linux/nfs3.h>
   8 #include <linux/nfs4.h>
   9 #include <linux/nfs_xdr.h>
  10 #include <linux/nfs_fs.h>
  11 #include "nfs4_fs.h"
  12 #include "nfs42.h"
  13
  14 static int nfs42_set_rw_stateid(nfs4_stateid *dst, struct file *file,
  15                                 fmode_t fmode)
  16 {
  17         struct nfs_open_context *open;
  18         struct nfs_lock_context *lock;
  19         int ret;
  20
  21         open = get_nfs_open_context(nfs_file_open_context(file));
  22         lock = nfs_get_lock_context(open);
  23         if (IS_ERR(lock)) {
  24                 put_nfs_open_context(open);
  25                 return PTR_ERR(lock);
  26         }
  27
  28         ret = nfs4_set_rw_stateid(dst, open, lock, fmode);
  29
  30         nfs_put_lock_context(lock);
  31         put_nfs_open_context(open);
  32         return ret;
  33 }
  34
  35 loff_t nfs42_proc_llseek(struct file *filep, loff_t offset, int whence)
  36 {
  37         struct inode *inode = file_inode(filep);
  38         struct nfs42_seek_args args = {
  39                 .sa_fh          = NFS_FH(inode),
  40                 .sa_offset      = offset,
  41                 .sa_what        = (whence == SEEK_HOLE) ?
  42                                         NFS4_CONTENT_HOLE : NFS4_CONTENT_DATA,
  43         };
  44         struct nfs42_seek_res res;
  45         struct rpc_message msg = {
  46                 .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SEEK],
  47                 .rpc_argp = &args,
  48                 .rpc_resp = &res,
  49         };
  50         struct nfs_server *server = NFS_SERVER(inode);
  51         int status;
  52
  53         if (!(server->caps & NFS_CAP_SEEK))
  54                 return -ENOTSUPP;
  55
  56         status = nfs42_set_rw_stateid(&args.sa_stateid, filep, FMODE_READ);
  57         if (status)
  58                 return status;
  59
  60         nfs_wb_all(inode);
  61         status = nfs4_call_sync(server->client, server, &msg,
  62                                 &args.seq_args, &res.seq_res, 0);
  63         if (status == -ENOTSUPP)
  64                 server->caps &= ~NFS_CAP_SEEK;
  65         if (status)
  66                 return status;
  67
  68         return vfs_setpos(filep, res.sr_offset, inode->i_sb->s_maxbytes);
  69 }