xref: /linux/fs/nfsd/blocklayoutxdr.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * Copyright (c) 2014 Christoph Hellwig.
3  */
4 #include <linux/sunrpc/svc.h>
5 #include <linux/exportfs.h>
6 #include <linux/nfs4.h>
7 
8 #include "nfsd.h"
9 #include "blocklayoutxdr.h"
10 
11 #define NFSDDBG_FACILITY	NFSDDBG_PNFS
12 
13 
14 __be32
15 nfsd4_block_encode_layoutget(struct xdr_stream *xdr,
16 		struct nfsd4_layoutget *lgp)
17 {
18 	struct pnfs_block_extent *b = lgp->lg_content;
19 	int len = sizeof(__be32) + 5 * sizeof(__be64) + sizeof(__be32);
20 	__be32 *p;
21 
22 	p = xdr_reserve_space(xdr, sizeof(__be32) + len);
23 	if (!p)
24 		return nfserr_toosmall;
25 
26 	*p++ = cpu_to_be32(len);
27 	*p++ = cpu_to_be32(1);		/* we always return a single extent */
28 
29 	p = xdr_encode_opaque_fixed(p, &b->vol_id,
30 			sizeof(struct nfsd4_deviceid));
31 	p = xdr_encode_hyper(p, b->foff);
32 	p = xdr_encode_hyper(p, b->len);
33 	p = xdr_encode_hyper(p, b->soff);
34 	*p++ = cpu_to_be32(b->es);
35 	return 0;
36 }
37 
38 static int
39 nfsd4_block_encode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b)
40 {
41 	__be32 *p;
42 	int len;
43 
44 	switch (b->type) {
45 	case PNFS_BLOCK_VOLUME_SIMPLE:
46 		len = 4 + 4 + 8 + 4 + b->simple.sig_len;
47 		p = xdr_reserve_space(xdr, len);
48 		if (!p)
49 			return -ETOOSMALL;
50 
51 		*p++ = cpu_to_be32(b->type);
52 		*p++ = cpu_to_be32(1);	/* single signature */
53 		p = xdr_encode_hyper(p, b->simple.offset);
54 		p = xdr_encode_opaque(p, b->simple.sig, b->simple.sig_len);
55 		break;
56 	default:
57 		return -ENOTSUPP;
58 	}
59 
60 	return len;
61 }
62 
63 __be32
64 nfsd4_block_encode_getdeviceinfo(struct xdr_stream *xdr,
65 		struct nfsd4_getdeviceinfo *gdp)
66 {
67 	struct pnfs_block_deviceaddr *dev = gdp->gd_device;
68 	int len = sizeof(__be32), ret, i;
69 	__be32 *p;
70 
71 	p = xdr_reserve_space(xdr, len + sizeof(__be32));
72 	if (!p)
73 		return nfserr_resource;
74 
75 	for (i = 0; i < dev->nr_volumes; i++) {
76 		ret = nfsd4_block_encode_volume(xdr, &dev->volumes[i]);
77 		if (ret < 0)
78 			return nfserrno(ret);
79 		len += ret;
80 	}
81 
82 	/*
83 	 * Fill in the overall length and number of volumes at the beginning
84 	 * of the layout.
85 	 */
86 	*p++ = cpu_to_be32(len);
87 	*p++ = cpu_to_be32(dev->nr_volumes);
88 	return 0;
89 }
90 
91 int
92 nfsd4_block_decode_layoutupdate(__be32 *p, u32 len, struct iomap **iomapp,
93 		u32 block_size)
94 {
95 	struct iomap *iomaps;
96 	u32 nr_iomaps, expected, i;
97 
98 	if (len < sizeof(u32)) {
99 		dprintk("%s: extent array too small: %u\n", __func__, len);
100 		return -EINVAL;
101 	}
102 
103 	nr_iomaps = be32_to_cpup(p++);
104 	expected = sizeof(__be32) + nr_iomaps * PNFS_BLOCK_EXTENT_SIZE;
105 	if (len != expected) {
106 		dprintk("%s: extent array size mismatch: %u/%u\n",
107 			__func__, len, expected);
108 		return -EINVAL;
109 	}
110 
111 	iomaps = kcalloc(nr_iomaps, sizeof(*iomaps), GFP_KERNEL);
112 	if (!iomaps) {
113 		dprintk("%s: failed to allocate extent array\n", __func__);
114 		return -ENOMEM;
115 	}
116 
117 	for (i = 0; i < nr_iomaps; i++) {
118 		struct pnfs_block_extent bex;
119 
120 		memcpy(&bex.vol_id, p, sizeof(struct nfsd4_deviceid));
121 		p += XDR_QUADLEN(sizeof(struct nfsd4_deviceid));
122 
123 		p = xdr_decode_hyper(p, &bex.foff);
124 		if (bex.foff & (block_size - 1)) {
125 			dprintk("%s: unaligned offset 0x%llx\n",
126 				__func__, bex.foff);
127 			goto fail;
128 		}
129 		p = xdr_decode_hyper(p, &bex.len);
130 		if (bex.len & (block_size - 1)) {
131 			dprintk("%s: unaligned length 0x%llx\n",
132 				__func__, bex.foff);
133 			goto fail;
134 		}
135 		p = xdr_decode_hyper(p, &bex.soff);
136 		if (bex.soff & (block_size - 1)) {
137 			dprintk("%s: unaligned disk offset 0x%llx\n",
138 				__func__, bex.soff);
139 			goto fail;
140 		}
141 		bex.es = be32_to_cpup(p++);
142 		if (bex.es != PNFS_BLOCK_READWRITE_DATA) {
143 			dprintk("%s: incorrect extent state %d\n",
144 				__func__, bex.es);
145 			goto fail;
146 		}
147 
148 		iomaps[i].offset = bex.foff;
149 		iomaps[i].length = bex.len;
150 	}
151 
152 	*iomapp = iomaps;
153 	return nr_iomaps;
154 fail:
155 	kfree(iomaps);
156 	return -EINVAL;
157 }
158