xref: /openbmc/linux/fs/nfs/nfs42proc.c (revision 609e478b)
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 }
70