xref: /linux/fs/nfsd/flexfilelayout.c (revision f4738f56d1dc62aaba69b33702a5ab098f1b8c63)
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 
22 static __be32
23 nfsd4_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 
75 out_error:
76 	seg->length = 0;
77 	return nfserrno(error);
78 }
79 
80 static __be32
81 nfsd4_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 
128 const 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