blocklayoutxdr.c

  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/**
 18 * nfsd4_block_encode_layoutget - encode block/scsi layout extent array
 19 * @xdr: stream for data encoding
 20 * @lgp: layoutget content, actually an array of extents to encode
 21 *
 22 * Encode the opaque loc_body field in the layoutget response. Since the
 23 * pnfs_block_layout4 and pnfs_scsi_layout4 structures on the wire are
 24 * the same, this function is used by both layout drivers.
 25 *
 26 * Return values:
 27 *   %nfs_ok: Success, all extents encoded into @xdr
 28 *   %nfserr_toosmall: Not enough space in @xdr to encode all the data
 29 */
 30__be32
 31nfsd4_block_encode_layoutget(struct xdr_stream *xdr,
 32		const struct nfsd4_layoutget *lgp)
 33{
 34	const struct pnfs_block_layout *bl = lgp->lg_content;
 35	u32 i, len = sizeof(__be32) + bl->nr_extents * PNFS_BLOCK_EXTENT_SIZE;
 36	__be32 *p;
 37
 38	p = xdr_reserve_space(xdr, sizeof(__be32) + len);
 39	if (!p)
 40		return nfserr_toosmall;
 41
 42	*p++ = cpu_to_be32(len);
 43	*p++ = cpu_to_be32(bl->nr_extents);
 44
 45	for (i = 0; i < bl->nr_extents; i++) {
 46		const struct pnfs_block_extent *bex = bl->extents + i;
 47
 48		p = svcxdr_encode_deviceid4(p, &bex->vol_id);
 49		p = xdr_encode_hyper(p, bex->foff);
 50		p = xdr_encode_hyper(p, bex->len);
 51		p = xdr_encode_hyper(p, bex->soff);
 52		*p++ = cpu_to_be32(bex->es);
 53	}
 54
 55	return nfs_ok;
 56}
 57
 58static int
 59nfsd4_block_encode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b)
 60{
 61	__be32 *p;
 62	int len;
 63
 64	switch (b->type) {
 65	case PNFS_BLOCK_VOLUME_SIMPLE:
 66		len = 4 + 4 + 8 + 4 + (XDR_QUADLEN(b->simple.sig_len) << 2);
 67		p = xdr_reserve_space(xdr, len);
 68		if (!p)
 69			return -ETOOSMALL;
 70
 71		*p++ = cpu_to_be32(b->type);
 72		*p++ = cpu_to_be32(1);	/* single signature */
 73		p = xdr_encode_hyper(p, b->simple.offset);
 74		p = xdr_encode_opaque(p, b->simple.sig, b->simple.sig_len);
 75		break;
 76	case PNFS_BLOCK_VOLUME_SCSI:
 77		len = 4 + 4 + 4 + 4 + (XDR_QUADLEN(b->scsi.designator_len) << 2) + 8;
 78		p = xdr_reserve_space(xdr, len);
 79		if (!p)
 80			return -ETOOSMALL;
 81
 82		*p++ = cpu_to_be32(b->type);
 83		*p++ = cpu_to_be32(b->scsi.code_set);
 84		*p++ = cpu_to_be32(b->scsi.designator_type);
 85		p = xdr_encode_opaque(p, b->scsi.designator, b->scsi.designator_len);
 86		p = xdr_encode_hyper(p, b->scsi.pr_key);
 87		break;
 88	default:
 89		return -ENOTSUPP;
 90	}
 91
 92	return len;
 93}
 94
 95__be32
 96nfsd4_block_encode_getdeviceinfo(struct xdr_stream *xdr,
 97		const struct nfsd4_getdeviceinfo *gdp)
 98{
 99	struct pnfs_block_deviceaddr *dev = gdp->gd_device;
100	int len = sizeof(__be32), ret, i;
101	__be32 *p;
102
103	/*
104	 * See paragraph 5 of RFC 8881 S18.40.3.
105	 */
106	if (!gdp->gd_maxcount) {
107		if (xdr_stream_encode_u32(xdr, 0) != XDR_UNIT)
108			return nfserr_resource;
109		return nfs_ok;
110	}
111
112	p = xdr_reserve_space(xdr, len + sizeof(__be32));
113	if (!p)
114		return nfserr_resource;
115
116	for (i = 0; i < dev->nr_volumes; i++) {
117		ret = nfsd4_block_encode_volume(xdr, &dev->volumes[i]);
118		if (ret < 0)
119			return nfserrno(ret);
120		len += ret;
121	}
122
123	/*
124	 * Fill in the overall length and number of volumes at the beginning
125	 * of the layout.
126	 */
127	*p++ = cpu_to_be32(len);
128	*p++ = cpu_to_be32(dev->nr_volumes);
129	return 0;
130}
131
132/**
133 * nfsd4_block_decode_layoutupdate - decode the block layout extent array
134 * @xdr: subbuf set to the encoded array
135 * @iomapp: pointer to store the decoded extent array
136 * @nr_iomapsp: pointer to store the number of extents
137 * @block_size: alignment of extent offset and length
138 *
139 * This function decodes the opaque field of the layoutupdate4 structure
140 * in a layoutcommit request for the block layout driver. The field is
141 * actually an array of extents sent by the client. It also checks that
142 * the file offset, storage offset and length of each extent are aligned
143 * by @block_size.
144 *
145 * Return values:
146 *   %nfs_ok: Successful decoding, @iomapp and @nr_iomapsp are valid
147 *   %nfserr_bad_xdr: The encoded array in @xdr is invalid
148 *   %nfserr_inval: An unaligned extent found
149 *   %nfserr_delay: Failed to allocate memory for @iomapp
150 */
151__be32
152nfsd4_block_decode_layoutupdate(struct xdr_stream *xdr, struct iomap **iomapp,
153		int *nr_iomapsp, u32 block_size)
154{
155	struct iomap *iomaps;
156	u32 nr_iomaps, expected, len, i;
157	__be32 nfserr;
158
159	if (xdr_stream_decode_u32(xdr, &nr_iomaps))
160		return nfserr_bad_xdr;
161
162	len = sizeof(__be32) + xdr_stream_remaining(xdr);
163	expected = sizeof(__be32) + nr_iomaps * PNFS_BLOCK_EXTENT_SIZE;
164	if (len != expected)
165		return nfserr_bad_xdr;
166
167	iomaps = kcalloc(nr_iomaps, sizeof(*iomaps), GFP_KERNEL);
168	if (!iomaps)
169		return nfserr_delay;
170
171	for (i = 0; i < nr_iomaps; i++) {
172		struct pnfs_block_extent bex;
173
174		if (nfsd4_decode_deviceid4(xdr, &bex.vol_id)) {
175			nfserr = nfserr_bad_xdr;
176			goto fail;
177		}
178
179		if (xdr_stream_decode_u64(xdr, &bex.foff)) {
180			nfserr = nfserr_bad_xdr;
181			goto fail;
182		}
183		if (bex.foff & (block_size - 1)) {
184			nfserr = nfserr_inval;
185			goto fail;
186		}
187
188		if (xdr_stream_decode_u64(xdr, &bex.len)) {
189			nfserr = nfserr_bad_xdr;
190			goto fail;
191		}
192		if (bex.len & (block_size - 1)) {
193			nfserr = nfserr_inval;
194			goto fail;
195		}
196
197		if (xdr_stream_decode_u64(xdr, &bex.soff)) {
198			nfserr = nfserr_bad_xdr;
199			goto fail;
200		}
201		if (bex.soff & (block_size - 1)) {
202			nfserr = nfserr_inval;
203			goto fail;
204		}
205
206		if (xdr_stream_decode_u32(xdr, &bex.es)) {
207			nfserr = nfserr_bad_xdr;
208			goto fail;
209		}
210		if (bex.es != PNFS_BLOCK_READWRITE_DATA) {
211			nfserr = nfserr_inval;
212			goto fail;
213		}
214
215		iomaps[i].offset = bex.foff;
216		iomaps[i].length = bex.len;
217	}
218
219	*iomapp = iomaps;
220	*nr_iomapsp = nr_iomaps;
221	return nfs_ok;
222fail:
223	kfree(iomaps);
224	return nfserr;
225}
226
227/**
228 * nfsd4_scsi_decode_layoutupdate - decode the scsi layout extent array
229 * @xdr: subbuf set to the encoded array
230 * @iomapp: pointer to store the decoded extent array
231 * @nr_iomapsp: pointer to store the number of extents
232 * @block_size: alignment of extent offset and length
233 *
234 * This function decodes the opaque field of the layoutupdate4 structure
235 * in a layoutcommit request for the scsi layout driver. The field is
236 * actually an array of extents sent by the client. It also checks that
237 * the offset and length of each extent are aligned by @block_size.
238 *
239 * Return values:
240 *   %nfs_ok: Successful decoding, @iomapp and @nr_iomapsp are valid
241 *   %nfserr_bad_xdr: The encoded array in @xdr is invalid
242 *   %nfserr_inval: An unaligned extent found
243 *   %nfserr_delay: Failed to allocate memory for @iomapp
244 */
245__be32
246nfsd4_scsi_decode_layoutupdate(struct xdr_stream *xdr, struct iomap **iomapp,
247		int *nr_iomapsp, u32 block_size)
248{
249	struct iomap *iomaps;
250	u32 nr_iomaps, expected, len, i;
251	__be32 nfserr;
252
253	if (xdr_stream_decode_u32(xdr, &nr_iomaps))
254		return nfserr_bad_xdr;
255
256	len = sizeof(__be32) + xdr_stream_remaining(xdr);
257	expected = sizeof(__be32) + nr_iomaps * PNFS_SCSI_RANGE_SIZE;
258	if (len != expected)
259		return nfserr_bad_xdr;
260
261	iomaps = kcalloc(nr_iomaps, sizeof(*iomaps), GFP_KERNEL);
262	if (!iomaps)
263		return nfserr_delay;
264
265	for (i = 0; i < nr_iomaps; i++) {
266		u64 val;
267
268		if (xdr_stream_decode_u64(xdr, &val)) {
269			nfserr = nfserr_bad_xdr;
270			goto fail;
271		}
272		if (val & (block_size - 1)) {
273			nfserr = nfserr_inval;
274			goto fail;
275		}
276		iomaps[i].offset = val;
277
278		if (xdr_stream_decode_u64(xdr, &val)) {
279			nfserr = nfserr_bad_xdr;
280			goto fail;
281		}
282		if (val & (block_size - 1)) {
283			nfserr = nfserr_inval;
284			goto fail;
285		}
286		iomaps[i].length = val;
287	}
288
289	*iomapp = iomaps;
290	*nr_iomapsp = nr_iomaps;
291	return nfs_ok;
292fail:
293	kfree(iomaps);
294	return nfserr;
295}