xref: /linux/fs/nfsd/blocklayoutxdr.c (revision 68a052239fc4b351e961f698b824f7654a346091)
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
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 = svcxdr_encode_deviceid4(p, &b->vol_id);
33 	p = xdr_encode_hyper(p, b->foff);
34 	p = xdr_encode_hyper(p, b->len);
35 	p = xdr_encode_hyper(p, b->soff);
36 	*p++ = cpu_to_be32(b->es);
37 	return 0;
38 }
39 
40 static int
41 nfsd4_block_encode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b)
42 {
43 	__be32 *p;
44 	int len;
45 
46 	switch (b->type) {
47 	case PNFS_BLOCK_VOLUME_SIMPLE:
48 		len = 4 + 4 + 8 + 4 + (XDR_QUADLEN(b->simple.sig_len) << 2);
49 		p = xdr_reserve_space(xdr, len);
50 		if (!p)
51 			return -ETOOSMALL;
52 
53 		*p++ = cpu_to_be32(b->type);
54 		*p++ = cpu_to_be32(1);	/* single signature */
55 		p = xdr_encode_hyper(p, b->simple.offset);
56 		p = xdr_encode_opaque(p, b->simple.sig, b->simple.sig_len);
57 		break;
58 	case PNFS_BLOCK_VOLUME_SCSI:
59 		len = 4 + 4 + 4 + 4 + (XDR_QUADLEN(b->scsi.designator_len) << 2) + 8;
60 		p = xdr_reserve_space(xdr, len);
61 		if (!p)
62 			return -ETOOSMALL;
63 
64 		*p++ = cpu_to_be32(b->type);
65 		*p++ = cpu_to_be32(b->scsi.code_set);
66 		*p++ = cpu_to_be32(b->scsi.designator_type);
67 		p = xdr_encode_opaque(p, b->scsi.designator, b->scsi.designator_len);
68 		p = xdr_encode_hyper(p, b->scsi.pr_key);
69 		break;
70 	default:
71 		return -ENOTSUPP;
72 	}
73 
74 	return len;
75 }
76 
77 __be32
78 nfsd4_block_encode_getdeviceinfo(struct xdr_stream *xdr,
79 		const struct nfsd4_getdeviceinfo *gdp)
80 {
81 	struct pnfs_block_deviceaddr *dev = gdp->gd_device;
82 	int len = sizeof(__be32), ret, i;
83 	__be32 *p;
84 
85 	/*
86 	 * See paragraph 5 of RFC 8881 S18.40.3.
87 	 */
88 	if (!gdp->gd_maxcount) {
89 		if (xdr_stream_encode_u32(xdr, 0) != XDR_UNIT)
90 			return nfserr_resource;
91 		return nfs_ok;
92 	}
93 
94 	p = xdr_reserve_space(xdr, len + sizeof(__be32));
95 	if (!p)
96 		return nfserr_resource;
97 
98 	for (i = 0; i < dev->nr_volumes; i++) {
99 		ret = nfsd4_block_encode_volume(xdr, &dev->volumes[i]);
100 		if (ret < 0)
101 			return nfserrno(ret);
102 		len += ret;
103 	}
104 
105 	/*
106 	 * Fill in the overall length and number of volumes at the beginning
107 	 * of the layout.
108 	 */
109 	*p++ = cpu_to_be32(len);
110 	*p++ = cpu_to_be32(dev->nr_volumes);
111 	return 0;
112 }
113 
114 /**
115  * nfsd4_block_decode_layoutupdate - decode the block layout extent array
116  * @xdr: subbuf set to the encoded array
117  * @iomapp: pointer to store the decoded extent array
118  * @nr_iomapsp: pointer to store the number of extents
119  * @block_size: alignment of extent offset and length
120  *
121  * This function decodes the opaque field of the layoutupdate4 structure
122  * in a layoutcommit request for the block layout driver. The field is
123  * actually an array of extents sent by the client. It also checks that
124  * the file offset, storage offset and length of each extent are aligned
125  * by @block_size.
126  *
127  * Return values:
128  *   %nfs_ok: Successful decoding, @iomapp and @nr_iomapsp are valid
129  *   %nfserr_bad_xdr: The encoded array in @xdr is invalid
130  *   %nfserr_inval: An unaligned extent found
131  *   %nfserr_delay: Failed to allocate memory for @iomapp
132  */
133 __be32
134 nfsd4_block_decode_layoutupdate(struct xdr_stream *xdr, struct iomap **iomapp,
135 		int *nr_iomapsp, u32 block_size)
136 {
137 	struct iomap *iomaps;
138 	u32 nr_iomaps, expected, len, i;
139 	__be32 nfserr;
140 
141 	if (xdr_stream_decode_u32(xdr, &nr_iomaps))
142 		return nfserr_bad_xdr;
143 
144 	len = sizeof(__be32) + xdr_stream_remaining(xdr);
145 	expected = sizeof(__be32) + nr_iomaps * PNFS_BLOCK_EXTENT_SIZE;
146 	if (len != expected)
147 		return nfserr_bad_xdr;
148 
149 	iomaps = kcalloc(nr_iomaps, sizeof(*iomaps), GFP_KERNEL);
150 	if (!iomaps)
151 		return nfserr_delay;
152 
153 	for (i = 0; i < nr_iomaps; i++) {
154 		struct pnfs_block_extent bex;
155 
156 		if (nfsd4_decode_deviceid4(xdr, &bex.vol_id)) {
157 			nfserr = nfserr_bad_xdr;
158 			goto fail;
159 		}
160 
161 		if (xdr_stream_decode_u64(xdr, &bex.foff)) {
162 			nfserr = nfserr_bad_xdr;
163 			goto fail;
164 		}
165 		if (bex.foff & (block_size - 1)) {
166 			nfserr = nfserr_inval;
167 			goto fail;
168 		}
169 
170 		if (xdr_stream_decode_u64(xdr, &bex.len)) {
171 			nfserr = nfserr_bad_xdr;
172 			goto fail;
173 		}
174 		if (bex.len & (block_size - 1)) {
175 			nfserr = nfserr_inval;
176 			goto fail;
177 		}
178 
179 		if (xdr_stream_decode_u64(xdr, &bex.soff)) {
180 			nfserr = nfserr_bad_xdr;
181 			goto fail;
182 		}
183 		if (bex.soff & (block_size - 1)) {
184 			nfserr = nfserr_inval;
185 			goto fail;
186 		}
187 
188 		if (xdr_stream_decode_u32(xdr, &bex.es)) {
189 			nfserr = nfserr_bad_xdr;
190 			goto fail;
191 		}
192 		if (bex.es != PNFS_BLOCK_READWRITE_DATA) {
193 			nfserr = nfserr_inval;
194 			goto fail;
195 		}
196 
197 		iomaps[i].offset = bex.foff;
198 		iomaps[i].length = bex.len;
199 	}
200 
201 	*iomapp = iomaps;
202 	*nr_iomapsp = nr_iomaps;
203 	return nfs_ok;
204 fail:
205 	kfree(iomaps);
206 	return nfserr;
207 }
208 
209 /**
210  * nfsd4_scsi_decode_layoutupdate - decode the scsi layout extent array
211  * @xdr: subbuf set to the encoded array
212  * @iomapp: pointer to store the decoded extent array
213  * @nr_iomapsp: pointer to store the number of extents
214  * @block_size: alignment of extent offset and length
215  *
216  * This function decodes the opaque field of the layoutupdate4 structure
217  * in a layoutcommit request for the scsi layout driver. The field is
218  * actually an array of extents sent by the client. It also checks that
219  * the offset and length of each extent are aligned by @block_size.
220  *
221  * Return values:
222  *   %nfs_ok: Successful decoding, @iomapp and @nr_iomapsp are valid
223  *   %nfserr_bad_xdr: The encoded array in @xdr is invalid
224  *   %nfserr_inval: An unaligned extent found
225  *   %nfserr_delay: Failed to allocate memory for @iomapp
226  */
227 __be32
228 nfsd4_scsi_decode_layoutupdate(struct xdr_stream *xdr, struct iomap **iomapp,
229 		int *nr_iomapsp, u32 block_size)
230 {
231 	struct iomap *iomaps;
232 	u32 nr_iomaps, expected, len, i;
233 	__be32 nfserr;
234 
235 	if (xdr_stream_decode_u32(xdr, &nr_iomaps))
236 		return nfserr_bad_xdr;
237 
238 	len = sizeof(__be32) + xdr_stream_remaining(xdr);
239 	expected = sizeof(__be32) + nr_iomaps * PNFS_SCSI_RANGE_SIZE;
240 	if (len != expected)
241 		return nfserr_bad_xdr;
242 
243 	iomaps = kcalloc(nr_iomaps, sizeof(*iomaps), GFP_KERNEL);
244 	if (!iomaps)
245 		return nfserr_delay;
246 
247 	for (i = 0; i < nr_iomaps; i++) {
248 		u64 val;
249 
250 		if (xdr_stream_decode_u64(xdr, &val)) {
251 			nfserr = nfserr_bad_xdr;
252 			goto fail;
253 		}
254 		if (val & (block_size - 1)) {
255 			nfserr = nfserr_inval;
256 			goto fail;
257 		}
258 		iomaps[i].offset = val;
259 
260 		if (xdr_stream_decode_u64(xdr, &val)) {
261 			nfserr = nfserr_bad_xdr;
262 			goto fail;
263 		}
264 		if (val & (block_size - 1)) {
265 			nfserr = nfserr_inval;
266 			goto fail;
267 		}
268 		iomaps[i].length = val;
269 	}
270 
271 	*iomapp = iomaps;
272 	*nr_iomapsp = nr_iomaps;
273 	return nfs_ok;
274 fail:
275 	kfree(iomaps);
276 	return nfserr;
277 }
278