1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2016 Tom Haynes <loghyr@primarydata.com>
4 *
5 * The following implements a super-simple flex-file server
6 * where the NFSv4.1 mds is also the ds. And the storage is
7 * the same. I.e., writing to the mds via a NFSv4.1 WRITE
8 * goes to the same location as the NFSv3 WRITE.
9 */
10#include <linux/slab.h>
11
12#include <linux/nfsd/debug.h>
13
14#include <linux/sunrpc/addr.h>
15
16#include "flexfilelayoutxdr.h"
17#include "pnfs.h"
18
19#define NFSDDBG_FACILITY	NFSDDBG_PNFS
20
21static __be32
22nfsd4_ff_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
23		struct nfsd4_layoutget *args)
24{
25	struct nfsd4_layout_seg *seg = &args->lg_seg;
26	u32 device_generation = 0;
27	int error;
28	uid_t u;
29
30	struct pnfs_ff_layout *fl;
31
32	/*
33	 * The super simple flex file server has 1 mirror, 1 data server,
34	 * and 1 file handle. So instead of 4 allocs, do 1 for now.
35	 * Zero it out for the stateid - don't want junk in there!
36	 */
37	error = -ENOMEM;
38	fl = kzalloc(sizeof(*fl), GFP_KERNEL);
39	if (!fl)
40		goto out_error;
41	args->lg_content = fl;
42
43	/*
44	 * Avoid layout commit, try to force the I/O to the DS,
45	 * and for fun, cause all IOMODE_RW layout segments to
46	 * effectively be WRITE only.
47	 */
48	fl->flags = FF_FLAGS_NO_LAYOUTCOMMIT | FF_FLAGS_NO_IO_THRU_MDS |
49		    FF_FLAGS_NO_READ_IO;
50
51	/* Do not allow a IOMODE_READ segment to have write pemissions */
52	if (seg->iomode == IOMODE_READ) {
53		u = from_kuid(&init_user_ns, inode->i_uid) + 1;
54		fl->uid = make_kuid(&init_user_ns, u);
55	} else
56		fl->uid = inode->i_uid;
57	fl->gid = inode->i_gid;
58
59	error = nfsd4_set_deviceid(&fl->deviceid, fhp, device_generation);
60	if (error)
61		goto out_error;
62
63	fl->fh.size = fhp->fh_handle.fh_size;
64	memcpy(fl->fh.data, &fhp->fh_handle.fh_base, fl->fh.size);
65
66	/* Give whole file layout segments */
67	seg->offset = 0;
68	seg->length = NFS4_MAX_UINT64;
69
70	dprintk("GET: 0x%llx:0x%llx %d\n", seg->offset, seg->length,
71		seg->iomode);
72	return 0;
73
74out_error:
75	seg->length = 0;
76	return nfserrno(error);
77}
78
79static __be32
80nfsd4_ff_proc_getdeviceinfo(struct super_block *sb, struct svc_rqst *rqstp,
81		struct nfs4_client *clp, struct nfsd4_getdeviceinfo *gdp)
82{
83	struct pnfs_ff_device_addr *da;
84
85	u16 port;
86	char addr[INET6_ADDRSTRLEN];
87
88	da = kzalloc(sizeof(struct pnfs_ff_device_addr), GFP_KERNEL);
89	if (!da)
90		return nfserrno(-ENOMEM);
91
92	gdp->gd_device = da;
93
94	da->version = 3;
95	da->minor_version = 0;
96
97	da->rsize = svc_max_payload(rqstp);
98	da->wsize = da->rsize;
99
100	rpc_ntop((struct sockaddr *)&rqstp->rq_daddr,
101		 addr, INET6_ADDRSTRLEN);
102	if (rqstp->rq_daddr.ss_family == AF_INET) {
103		struct sockaddr_in *sin;
104
105		sin = (struct sockaddr_in *)&rqstp->rq_daddr;
106		port = ntohs(sin->sin_port);
107		snprintf(da->netaddr.netid, FF_NETID_LEN + 1, "tcp");
108		da->netaddr.netid_len = 3;
109	} else {
110		struct sockaddr_in6 *sin6;
111
112		sin6 = (struct sockaddr_in6 *)&rqstp->rq_daddr;
113		port = ntohs(sin6->sin6_port);
114		snprintf(da->netaddr.netid, FF_NETID_LEN + 1, "tcp6");
115		da->netaddr.netid_len = 4;
116	}
117
118	da->netaddr.addr_len =
119		snprintf(da->netaddr.addr, FF_ADDR_LEN + 1,
120			 "%s.%hhu.%hhu", addr, port >> 8, port & 0xff);
121
122	da->tightly_coupled = false;
123
124	return 0;
125}
126
127const struct nfsd4_layout_ops ff_layout_ops = {
128	.notify_types		=
129			NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
130	.disable_recalls	= true,
131	.proc_getdeviceinfo	= nfsd4_ff_proc_getdeviceinfo,
132	.encode_getdeviceinfo	= nfsd4_ff_encode_getdeviceinfo,
133	.proc_layoutget		= nfsd4_ff_proc_layoutget,
134	.encode_layoutget	= nfsd4_ff_encode_layoutget,
135};
136