aboutsummaryrefslogtreecommitdiff
path: root/net/sunrpc/xprtrdma/svc_rdma_marshal.c
blob: 8d2edddf48cf13c6d283bd8784e61c7601f23fc7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
/*
 * Copyright (c) 2005-2006 Network Appliance, Inc. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the BSD-type
 * license below:
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *      Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *      Redistributions in binary form must reproduce the above
 *      copyright notice, this list of conditions and the following
 *      disclaimer in the documentation and/or other materials provided
 *      with the distribution.
 *
 *      Neither the name of the Network Appliance, Inc. nor the names of
 *      its contributors may be used to endorse or promote products
 *      derived from this software without specific prior written
 *      permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Author: Tom Tucker <tom@opengridcomputing.com>
 */

#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/debug.h>
#include <asm/unaligned.h>
#include <linux/sunrpc/rpc_rdma.h>
#include <linux/sunrpc/svc_rdma.h>

#define RPCDBG_FACILITY	RPCDBG_SVCXPRT

/*
 * Decodes a read chunk list. The expected format is as follows:
 *    descrim  : xdr_one
 *    position : u32 offset into XDR stream
 *    handle   : u32 RKEY
 *    . . .
 *  end-of-list: xdr_zero
 */
static u32 *decode_read_list(u32 *va, u32 *vaend)
{
	struct rpcrdma_read_chunk *ch = (struct rpcrdma_read_chunk *)va;

	while (ch->rc_discrim != xdr_zero) {
		if (((unsigned long)ch + sizeof(struct rpcrdma_read_chunk)) >
		    (unsigned long)vaend) {
			dprintk("svcrdma: vaend=%p, ch=%p\n", vaend, ch);
			return NULL;
		}
		ch++;
	}
	return (u32 *)&ch->rc_position;
}

/*
 * Determine number of chunks and total bytes in chunk list. The chunk
 * list has already been verified to fit within the RPCRDMA header.
 */
void svc_rdma_rcl_chunk_counts(struct rpcrdma_read_chunk *ch,
			       int *ch_count, int *byte_count)
{
	/* compute the number of bytes represented by read chunks */
	*byte_count = 0;
	*ch_count = 0;
	for (; ch->rc_discrim != 0; ch++) {
		*byte_count = *byte_count + ntohl(ch->rc_target.rs_length);
		*ch_count = *ch_count + 1;
	}
}

/*
 * Decodes a write chunk list. The expected format is as follows:
 *    descrim  : xdr_one
 *    nchunks  : <count>
 *       handle   : u32 RKEY              ---+
 *       length   : u32 <len of segment>     |
 *       offset   : remove va                + <count>
 *       . . .                               |
 *                                        ---+
 */
static u32 *decode_write_list(u32 *va, u32 *vaend)
{
	int nchunks;

	struct rpcrdma_write_array *ary =
		(struct rpcrdma_write_array *)va;

	/* Check for not write-array */
	if (ary->wc_discrim == xdr_zero)
		return (u32 *)&ary->wc_nchunks;

	if ((unsigned long)ary + sizeof(struct rpcrdma_write_array) >
	    (unsigned long)vaend) {
		dprintk("svcrdma: ary=%p, vaend=%p\n", ary, vaend);
		return NULL;
	}
	nchunks = ntohl(ary->wc_nchunks);
	if (((unsigned long)&ary->wc_array[0] +
	     (sizeof(struct rpcrdma_write_chunk) * nchunks)) >
	    (unsigned long)vaend) {
		dprintk("svcrdma: ary=%p, wc_nchunks=%d, vaend=%p\n",
			ary, nchunks, vaend);
		return NULL;
	}
	/*
	 * rs_length is the 2nd 4B field in wc_target and taking its
	 * address skips the list terminator
	 */
	return (u32 *)&ary->wc_array[nchunks].wc_target.rs_length;
}

static u32 *decode_reply_array(u32 *va, u32 *vaend)
{
	int nchunks;
	struct rpcrdma_write_array *ary =
		(struct rpcrdma_write_array *)va;

	/* Check for no reply-array */
	if (ary->wc_discrim == xdr_zero)
		return (u32 *)&ary->wc_nchunks;

	if ((unsigned long)ary + sizeof(struct rpcrdma_write_array) >
	    (unsigned long)vaend) {
		dprintk("svcrdma: ary=%p, vaend=%p\n", ary, vaend);
		return NULL;
	}
	nchunks = ntohl(ary->wc_nchunks);
	if (((unsigned long)&ary->wc_array[0] +
	     (sizeof(struct rpcrdma_write_chunk) * nchunks)) >
	    (unsigned long)vaend) {
		dprintk("svcrdma: ary=%p, wc_nchunks=%d, vaend=%p\n",
			ary, nchunks, vaend);
		return NULL;
	}
	return (u32 *)&ary->wc_array[nchunks];
}

int svc_rdma_xdr_decode_req(struct rpcrdma_msg **rdma_req,
			    struct svc_rqst *rqstp)
{
	struct rpcrdma_msg *rmsgp = NULL;
	u32 *va;
	u32 *vaend;
	u32 hdr_len;

	rmsgp = (struct rpcrdma_msg *)rqstp->rq_arg.head[0].iov_base;

	/* Verify that there's enough bytes for header + something */
	if (rqstp->rq_arg.len <= RPCRDMA_HDRLEN_MIN) {
		dprintk("svcrdma: header too short = %d\n",
			rqstp->rq_arg.len);
		return -EINVAL;
	}

	/* Decode the header */
	rmsgp->rm_xid = ntohl(rmsgp->rm_xid);
	rmsgp->rm_vers = ntohl(rmsgp->rm_vers);
	rmsgp->rm_credit = ntohl(rmsgp->rm_credit);
	rmsgp->rm_type = ntohl(rmsgp->rm_type);

	if (rmsgp->rm_vers != RPCRDMA_VERSION)
		return -ENOSYS;

	/* Pull in the extra for the padded case and bump our pointer */
	if (rmsgp->rm_type == RDMA_MSGP) {
		int hdrlen;
		rmsgp->rm_body.rm_padded.rm_align =
			ntohl(rmsgp->rm_body.rm_padded.rm_align);
		rmsgp->rm_body.rm_padded.rm_thresh =
			ntohl(rmsgp->rm_body.rm_padded.rm_thresh);

		va = &rmsgp->rm_body.rm_padded.rm_pempty[4];
		rqstp->rq_arg.head[0].iov_base = va;
		hdrlen = (u32)((unsigned long)va - (unsigned long)rmsgp);
		rqstp->rq_arg.head[0].iov_len -= hdrlen;
		if (hdrlen > rqstp->rq_arg.len)
			return -EINVAL;
		return hdrlen;
	}

	/* The chunk list may contain either a read chunk list or a write
	 * chunk list and a reply chunk list.
	 */
	va = &rmsgp->rm_body.rm_chunks[0];
	vaend = (u32 *)((unsigned long)rmsgp + rqstp->rq_arg.len);
	va = decode_read_list(va, vaend);
	if (!va)
		return -EINVAL;
	va = decode_write_list(va, vaend);
	if (!va)
		return -EINVAL;
	va = decode_reply_array(va, vaend);
	if (!va)
		return -EINVAL;

	rqstp->rq_arg.head[0].iov_base = va;
	hdr_len = (unsigned long)va - (unsigned long)rmsgp;
	rqstp->rq_arg.head[0].iov_len -= hdr_len;

	*rdma_req = rmsgp;
	return hdr_len;
}

int svc_rdma_xdr_decode_deferred_req(struct svc_rqst *rqstp)
{
	struct rpcrdma_msg *rmsgp = NULL;
	struct rpcrdma_read_chunk *ch;
	struct rpcrdma_write_array *ary;
	u32 *va;
	u32 hdrlen;

	dprintk("svcrdma: processing deferred RDMA header on rqstp=%p\n",
		rqstp);
	rmsgp = (struct rpcrdma_msg *)rqstp->rq_arg.head[0].iov_base;

	/* Pull in the extra for the padded case and bump our pointer */
	if (rmsgp->rm_type == RDMA_MSGP) {
		va = &rmsgp->rm_body.rm_padded.rm_pempty[4];
		rqstp->rq_arg.head[0].iov_base = va;
		hdrlen = (u32)((unsigned long)va - (unsigned long)rmsgp);
		rqstp->rq_arg.head[0].iov_len -= hdrlen;
		return hdrlen;
	}

	/*
	 * Skip all chunks to find RPC msg. These were previously processed
	 */
	va = &rmsgp->rm_body.rm_chunks[0];

	/* Skip read-list */
	for (ch = (struct rpcrdma_read_chunk *)va;
	     ch->rc_discrim != xdr_zero; ch++);
	va = (u32 *)&ch->rc_position;

	/* Skip write-list */
	ary = (struct rpcrdma_write_array *)va;
	if (ary->wc_discrim == xdr_zero)
		va = (u32 *)&ary->wc_nchunks;
	else
		/*
		 * rs_length is the 2nd 4B field in wc_target and taking its
		 * address skips the list terminator
		 */
		va = (u32 *)&ary->wc_array[ary->wc_nchunks].wc_target.rs_length;

	/* Skip reply-array */
	ary = (struct rpcrdma_write_array *)va;
	if (ary->wc_discrim == xdr_zero)
		va = (u32 *)&ary->wc_nchunks;
	else
		va = (u32 *)&ary->wc_array[ary->wc_nchunks];

	rqstp->rq_arg.head[0].iov_base = va;
	hdrlen = (unsigned long)va - (unsigned long)rmsgp;
	rqstp->rq_arg.head[0].iov_len -= hdrlen;

	return hdrlen;
}

int svc_rdma_xdr_encode_error(struct svcxprt_rdma *xprt,
			      struct rpcrdma_msg *rmsgp,
			      enum rpcrdma_errcode err, u32 *va)
{
	u32 *startp = va;

	*va++ = htonl(rmsgp->rm_xid);
	*va++ = htonl(rmsgp->rm_vers);
	*va++ = htonl(xprt->sc_max_requests);
	*va++ = htonl(RDMA_ERROR);
	*va++ = htonl(err);
	if (err == ERR_VERS) {
		*va++ = htonl(RPCRDMA_VERSION);
		*va++ = htonl(RPCRDMA_VERSION);
	}

	return (int)((unsigned long)va - (unsigned long)startp);
}

int svc_rdma_xdr_get_reply_hdr_len(struct rpcrdma_msg *rmsgp)
{
	struct rpcrdma_write_array *wr_ary;

	/* There is no read-list in a reply */

	/* skip write list */
	wr_ary = (struct rpcrdma_write_array *)
		&rmsgp->rm_body.rm_chunks[1];
	if (wr_ary->wc_discrim)
		wr_ary = (struct rpcrdma_write_array *)
			&wr_ary->wc_array[ntohl(wr_ary->wc_nchunks)].
			wc_target.rs_length;
	else
		wr_ary = (struct rpcrdma_write_array *)
			&wr_ary->wc_nchunks;

	/* skip reply array */
	if (wr_ary->wc_discrim)
		wr_ary = (struct rpcrdma_write_array *)
			&wr_ary->wc_array[ntohl(wr_ary->wc_nchunks)];
	else
		wr_ary = (struct rpcrdma_write_array *)
			&wr_ary->wc_nchunks;

	return (unsigned long) wr_ary - (unsigned long) rmsgp;
}

void svc_rdma_xdr_encode_write_list(struct rpcrdma_msg *rmsgp, int chunks)
{
	struct rpcrdma_write_array *ary;

	/* no read-list */
	rmsgp->rm_body.rm_chunks[0] = xdr_zero;

	/* write-array discrim */
	ary = (struct rpcrdma_write_array *)
		&rmsgp->rm_body.rm_chunks[1];
	ary->wc_discrim = xdr_one;
	ary->wc_nchunks = htonl(chunks);

	/* write-list terminator */
	ary->wc_array[chunks].wc_target.rs_handle = xdr_zero;

	/* reply-array discriminator */
	ary->wc_array[chunks].wc_target.rs_length = xdr_zero;
}

void svc_rdma_xdr_encode_reply_array(struct rpcrdma_write_array *ary,
				 int chunks)
{
	ary->wc_discrim = xdr_one;
	ary->wc_nchunks = htonl(chunks);
}

void svc_rdma_xdr_encode_array_chunk(struct rpcrdma_write_array *ary,
				     int chunk_no,
				     __be32 rs_handle,
				     __be64 rs_offset,
				     u32 write_len)
{
	struct rpcrdma_segment *seg = &ary->wc_array[chunk_no].wc_target;
	seg->rs_handle = rs_handle;
	seg->rs_offset = rs_offset;
	seg->rs_length = htonl(write_len);
}

void svc_rdma_xdr_encode_reply_header(struct svcxprt_rdma *xprt,
				  struct rpcrdma_msg *rdma_argp,
				  struct rpcrdma_msg *rdma_resp,
				  enum rpcrdma_proc rdma_type)
{
	rdma_resp->rm_xid = htonl(rdma_argp->rm_xid);
	rdma_resp->rm_vers = htonl(rdma_argp->rm_vers);
	rdma_resp->rm_credit = htonl(xprt->sc_max_requests);
	rdma_resp->rm_type = htonl(rdma_type);

	/* Encode <nul> chunks lists */
	rdma_resp->rm_body.rm_chunks[0] = xdr_zero;
	rdma_resp->rm_body.rm_chunks[1] = xdr_zero;
	rdma_resp->rm_body.rm_chunks[2] = xdr_zero;
}