xref: /linux/fs/nfsd/flexfilelayout.c (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
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 
21 static __be32
22 nfsd4_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 
74 out_error:
75 	seg->length = 0;
76 	return nfserrno(error);
77 }
78 
79 static __be32
80 nfsd4_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 
127 const 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