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#include "vfs.h"
19
20#define NFSDDBG_FACILITY	NFSDDBG_PNFS
21
22static __be32
23nfsd4_ff_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
24		struct nfsd4_layoutget *args)
25{
26	struct nfsd4_layout_seg *seg = &args->lg_seg;
27	u32 device_generation = 0;
28	int error;
29	uid_t u;
30
31	struct pnfs_ff_layout *fl;
32
33	/*
34	 * The super simple flex file server has 1 mirror, 1 data server,
35	 * and 1 file handle. So instead of 4 allocs, do 1 for now.
36	 * Zero it out for the stateid - don't want junk in there!
37	 */
38	error = -ENOMEM;
39	fl = kzalloc(sizeof(*fl), GFP_KERNEL);
40	if (!fl)
41		goto out_error;
42	args->lg_content = fl;
43
44	/*
45	 * Avoid layout commit, try to force the I/O to the DS,
46	 * and for fun, cause all IOMODE_RW layout segments to
47	 * effectively be WRITE only.
48	 */
49	fl->flags = FF_FLAGS_NO_LAYOUTCOMMIT | FF_FLAGS_NO_IO_THRU_MDS |
50		    FF_FLAGS_NO_READ_IO;
51
52	/* Do not allow a IOMODE_READ segment to have write pemissions */
53	if (seg->iomode == IOMODE_READ) {
54		u = from_kuid(&init_user_ns, inode->i_uid) + 1;
55		fl->uid = make_kuid(&init_user_ns, u);
56	} else
57		fl->uid = inode->i_uid;
58	fl->gid = inode->i_gid;
59
60	error = nfsd4_set_deviceid(&fl->deviceid, fhp, device_generation);
61	if (error)
62		goto out_error;
63
64	fl->fh.size = fhp->fh_handle.fh_size;
65	memcpy(fl->fh.data, &fhp->fh_handle.fh_raw, fl->fh.size);
66
67	/* Give whole file layout segments */
68	seg->offset = 0;
69	seg->length = NFS4_MAX_UINT64;
70
71	dprintk("GET: 0x%llx:0x%llx %d\n", seg->offset, seg->length,
72		seg->iomode);
73	return 0;
74
75out_error:
76	seg->length = 0;
77	return nfserrno(error);
78}
79
80static __be32
81nfsd4_ff_proc_getdeviceinfo(struct super_block *sb, struct svc_rqst *rqstp,
82		struct nfs4_client *clp, struct nfsd4_getdeviceinfo *gdp)
83{
84	struct pnfs_ff_device_addr *da;
85
86	u16 port;
87	char addr[INET6_ADDRSTRLEN];
88
89	da = kzalloc(sizeof(struct pnfs_ff_device_addr), GFP_KERNEL);
90	if (!da)
91		return nfserrno(-ENOMEM);
92
93	gdp->gd_device = da;
94
95	da->version = 3;
96	da->minor_version = 0;
97
98	da->rsize = svc_max_payload(rqstp);
99	da->wsize = da->rsize;
100
101	rpc_ntop((struct sockaddr *)&rqstp->rq_daddr,
102		 addr, INET6_ADDRSTRLEN);
103	if (rqstp->rq_daddr.ss_family == AF_INET) {
104		struct sockaddr_in *sin;
105
106		sin = (struct sockaddr_in *)&rqstp->rq_daddr;
107		port = ntohs(sin->sin_port);
108		snprintf(da->netaddr.netid, FF_NETID_LEN + 1, "tcp");
109		da->netaddr.netid_len = 3;
110	} else {
111		struct sockaddr_in6 *sin6;
112
113		sin6 = (struct sockaddr_in6 *)&rqstp->rq_daddr;
114		port = ntohs(sin6->sin6_port);
115		snprintf(da->netaddr.netid, FF_NETID_LEN + 1, "tcp6");
116		da->netaddr.netid_len = 4;
117	}
118
119	da->netaddr.addr_len =
120		snprintf(da->netaddr.addr, FF_ADDR_LEN + 1,
121			 "%s.%d.%d", addr, port >> 8, port & 0xff);
122
123	da->tightly_coupled = false;
124
125	return 0;
126}
127
128const struct nfsd4_layout_ops ff_layout_ops = {
129	.notify_types		=
130			NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
131	.disable_recalls	= true,
132	.proc_getdeviceinfo	= nfsd4_ff_proc_getdeviceinfo,
133	.encode_getdeviceinfo	= nfsd4_ff_encode_getdeviceinfo,
134	.proc_layoutget		= nfsd4_ff_proc_layoutget,
135	.encode_layoutget	= nfsd4_ff_encode_layoutget,
136};
137