xref: /linux/fs/nfsd/blocklayoutxdr.c (revision ce3f5bb7504ca802efa710280a4601a06545bd2e)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2014-2016 Christoph Hellwig.
4  */
5 #include <linux/sunrpc/svc.h>
6 #include <linux/exportfs.h>
7 #include <linux/iomap.h>
8 #include <linux/nfs4.h>
9 
10 #include "nfsd.h"
11 #include "blocklayoutxdr.h"
12 #include "vfs.h"
13 
14 #define NFSDDBG_FACILITY	NFSDDBG_PNFS
15 
16 
17 __be32
nfsd4_block_encode_layoutget(struct xdr_stream * xdr,const struct nfsd4_layoutget * lgp)18 nfsd4_block_encode_layoutget(struct xdr_stream *xdr,
19 		const struct nfsd4_layoutget *lgp)
20 {
21 	const struct pnfs_block_extent *b = lgp->lg_content;
22 	int len = sizeof(__be32) + 5 * sizeof(__be64) + sizeof(__be32);
23 	__be32 *p;
24 
25 	p = xdr_reserve_space(xdr, sizeof(__be32) + len);
26 	if (!p)
27 		return nfserr_toosmall;
28 
29 	*p++ = cpu_to_be32(len);
30 	*p++ = cpu_to_be32(1);		/* we always return a single extent */
31 
32 	p = xdr_encode_opaque_fixed(p, &b->vol_id,
33 			sizeof(struct nfsd4_deviceid));
34 	p = xdr_encode_hyper(p, b->foff);
35 	p = xdr_encode_hyper(p, b->len);
36 	p = xdr_encode_hyper(p, b->soff);
37 	*p++ = cpu_to_be32(b->es);
38 	return 0;
39 }
40 
41 static int
nfsd4_block_encode_volume(struct xdr_stream * xdr,struct pnfs_block_volume * b)42 nfsd4_block_encode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b)
43 {
44 	__be32 *p;
45 	int len;
46 
47 	switch (b->type) {
48 	case PNFS_BLOCK_VOLUME_SIMPLE:
49 		len = 4 + 4 + 8 + 4 + (XDR_QUADLEN(b->simple.sig_len) << 2);
50 		p = xdr_reserve_space(xdr, len);
51 		if (!p)
52 			return -ETOOSMALL;
53 
54 		*p++ = cpu_to_be32(b->type);
55 		*p++ = cpu_to_be32(1);	/* single signature */
56 		p = xdr_encode_hyper(p, b->simple.offset);
57 		p = xdr_encode_opaque(p, b->simple.sig, b->simple.sig_len);
58 		break;
59 	case PNFS_BLOCK_VOLUME_SCSI:
60 		len = 4 + 4 + 4 + 4 + (XDR_QUADLEN(b->scsi.designator_len) << 2) + 8;
61 		p = xdr_reserve_space(xdr, len);
62 		if (!p)
63 			return -ETOOSMALL;
64 
65 		*p++ = cpu_to_be32(b->type);
66 		*p++ = cpu_to_be32(b->scsi.code_set);
67 		*p++ = cpu_to_be32(b->scsi.designator_type);
68 		p = xdr_encode_opaque(p, b->scsi.designator, b->scsi.designator_len);
69 		p = xdr_encode_hyper(p, b->scsi.pr_key);
70 		break;
71 	default:
72 		return -ENOTSUPP;
73 	}
74 
75 	return len;
76 }
77 
78 __be32
nfsd4_block_encode_getdeviceinfo(struct xdr_stream * xdr,const struct nfsd4_getdeviceinfo * gdp)79 nfsd4_block_encode_getdeviceinfo(struct xdr_stream *xdr,
80 		const struct nfsd4_getdeviceinfo *gdp)
81 {
82 	struct pnfs_block_deviceaddr *dev = gdp->gd_device;
83 	int len = sizeof(__be32), ret, i;
84 	__be32 *p;
85 
86 	/*
87 	 * See paragraph 5 of RFC 8881 S18.40.3.
88 	 */
89 	if (!gdp->gd_maxcount) {
90 		if (xdr_stream_encode_u32(xdr, 0) != XDR_UNIT)
91 			return nfserr_resource;
92 		return nfs_ok;
93 	}
94 
95 	p = xdr_reserve_space(xdr, len + sizeof(__be32));
96 	if (!p)
97 		return nfserr_resource;
98 
99 	for (i = 0; i < dev->nr_volumes; i++) {
100 		ret = nfsd4_block_encode_volume(xdr, &dev->volumes[i]);
101 		if (ret < 0)
102 			return nfserrno(ret);
103 		len += ret;
104 	}
105 
106 	/*
107 	 * Fill in the overall length and number of volumes at the beginning
108 	 * of the layout.
109 	 */
110 	*p++ = cpu_to_be32(len);
111 	*p++ = cpu_to_be32(dev->nr_volumes);
112 	return 0;
113 }
114 
115 /**
116  * nfsd4_block_decode_layoutupdate - decode the block layout extent array
117  * @p: pointer to the xdr data
118  * @len: number of bytes to decode
119  * @iomapp: pointer to store the decoded extent array
120  * @nr_iomapsp: pointer to store the number of extents
121  * @block_size: alignment of extent offset and length
122  *
123  * This function decodes the opaque field of the layoutupdate4 structure
124  * in a layoutcommit request for the block layout driver. The field is
125  * actually an array of extents sent by the client. It also checks that
126  * the file offset, storage offset and length of each extent are aligned
127  * by @block_size.
128  *
129  * Return values:
130  *   %nfs_ok: Successful decoding, @iomapp and @nr_iomapsp are valid
131  *   %nfserr_bad_xdr: The encoded array in @p is invalid
132  *   %nfserr_inval: An unaligned extent found
133  *   %nfserr_delay: Failed to allocate memory for @iomapp
134  */
135 __be32
nfsd4_block_decode_layoutupdate(__be32 * p,u32 len,struct iomap ** iomapp,int * nr_iomapsp,u32 block_size)136 nfsd4_block_decode_layoutupdate(__be32 *p, u32 len, struct iomap **iomapp,
137 		int *nr_iomapsp, u32 block_size)
138 {
139 	struct iomap *iomaps;
140 	u32 nr_iomaps, i;
141 
142 	if (len < sizeof(u32))
143 		return nfserr_bad_xdr;
144 	len -= sizeof(u32);
145 	if (len % PNFS_BLOCK_EXTENT_SIZE)
146 		return nfserr_bad_xdr;
147 
148 	nr_iomaps = be32_to_cpup(p++);
149 	if (nr_iomaps != len / PNFS_BLOCK_EXTENT_SIZE)
150 		return nfserr_bad_xdr;
151 
152 	iomaps = kcalloc(nr_iomaps, sizeof(*iomaps), GFP_KERNEL);
153 	if (!iomaps)
154 		return nfserr_delay;
155 
156 	for (i = 0; i < nr_iomaps; i++) {
157 		struct pnfs_block_extent bex;
158 
159 		memcpy(&bex.vol_id, p, sizeof(struct nfsd4_deviceid));
160 		p += XDR_QUADLEN(sizeof(struct nfsd4_deviceid));
161 
162 		p = xdr_decode_hyper(p, &bex.foff);
163 		if (bex.foff & (block_size - 1)) {
164 			goto fail;
165 		}
166 		p = xdr_decode_hyper(p, &bex.len);
167 		if (bex.len & (block_size - 1)) {
168 			goto fail;
169 		}
170 		p = xdr_decode_hyper(p, &bex.soff);
171 		if (bex.soff & (block_size - 1)) {
172 			goto fail;
173 		}
174 		bex.es = be32_to_cpup(p++);
175 		if (bex.es != PNFS_BLOCK_READWRITE_DATA) {
176 			goto fail;
177 		}
178 
179 		iomaps[i].offset = bex.foff;
180 		iomaps[i].length = bex.len;
181 	}
182 
183 	*iomapp = iomaps;
184 	*nr_iomapsp = nr_iomaps;
185 	return nfs_ok;
186 fail:
187 	kfree(iomaps);
188 	return nfserr_inval;
189 }
190 
191 /**
192  * nfsd4_scsi_decode_layoutupdate - decode the scsi layout extent array
193  * @p: pointer to the xdr data
194  * @len: number of bytes to decode
195  * @iomapp: pointer to store the decoded extent array
196  * @nr_iomapsp: pointer to store the number of extents
197  * @block_size: alignment of extent offset and length
198  *
199  * This function decodes the opaque field of the layoutupdate4 structure
200  * in a layoutcommit request for the scsi layout driver. The field is
201  * actually an array of extents sent by the client. It also checks that
202  * the offset and length of each extent are aligned by @block_size.
203  *
204  * Return values:
205  *   %nfs_ok: Successful decoding, @iomapp and @nr_iomapsp are valid
206  *   %nfserr_bad_xdr: The encoded array in @p is invalid
207  *   %nfserr_inval: An unaligned extent found
208  *   %nfserr_delay: Failed to allocate memory for @iomapp
209  */
210 __be32
nfsd4_scsi_decode_layoutupdate(__be32 * p,u32 len,struct iomap ** iomapp,int * nr_iomapsp,u32 block_size)211 nfsd4_scsi_decode_layoutupdate(__be32 *p, u32 len, struct iomap **iomapp,
212 		int *nr_iomapsp, u32 block_size)
213 {
214 	struct iomap *iomaps;
215 	u32 nr_iomaps, expected, i;
216 
217 	if (len < sizeof(u32))
218 		return nfserr_bad_xdr;
219 
220 	nr_iomaps = be32_to_cpup(p++);
221 	expected = sizeof(__be32) + nr_iomaps * PNFS_SCSI_RANGE_SIZE;
222 	if (len != expected)
223 		return nfserr_bad_xdr;
224 
225 	iomaps = kcalloc(nr_iomaps, sizeof(*iomaps), GFP_KERNEL);
226 	if (!iomaps)
227 		return nfserr_delay;
228 
229 	for (i = 0; i < nr_iomaps; i++) {
230 		u64 val;
231 
232 		p = xdr_decode_hyper(p, &val);
233 		if (val & (block_size - 1)) {
234 			goto fail;
235 		}
236 		iomaps[i].offset = val;
237 
238 		p = xdr_decode_hyper(p, &val);
239 		if (val & (block_size - 1)) {
240 			goto fail;
241 		}
242 		iomaps[i].length = val;
243 	}
244 
245 	*iomapp = iomaps;
246 	*nr_iomapsp = nr_iomaps;
247 	return nfs_ok;
248 fail:
249 	kfree(iomaps);
250 	return nfserr_inval;
251 }
252