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(size: 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(to: &init_user_ns, uid: inode->i_uid) + 1;
55 fl->uid = make_kuid(from: &init_user_ns, uid: u);
56 } else
57 fl->uid = inode->i_uid;
58 fl->gid = inode->i_gid;
59
60 error = nfsd4_set_deviceid(id: &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(errno: 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(size: sizeof(struct pnfs_ff_device_addr), GFP_KERNEL);
90 if (!da)
91 return nfserrno(errno: -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(buf: da->netaddr.netid, FF_NETID_LEN + 1, fmt: "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(buf: da->netaddr.netid, FF_NETID_LEN + 1, fmt: "tcp6");
116 da->netaddr.netid_len = 4;
117 }
118
119 da->netaddr.addr_len =
120 snprintf(buf: da->netaddr.addr, FF_ADDR_LEN + 1,
121 fmt: "%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

source code of linux/fs/nfsd/flexfilelayout.c