1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2009-2011 Spectra Logic Corporation
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions, and the following disclaimer,
12  *    without modification.
13  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
14  *    substantially similar to the "NO WARRANTY" disclaimer below
15  *    ("Disclaimer") and any redistribution must be conditioned upon
16  *    including a substantially similar Disclaimer requirement for further
17  *    binary redistribution.
18  *
19  * NO WARRANTY
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
23  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
24  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
28  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
29  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGES.
31  *
32  * Authors: Justin T. Gibbs     (Spectra Logic Corporation)
33  *          Alan Somers         (Spectra Logic Corporation)
34  *          John Suykerbuyk     (Spectra Logic Corporation)
35  */
36 
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 /**
41  * \file netback_unit_tests.c
42  *
43  * \brief Unit tests for the Xen netback driver.
44  *
45  * Due to the driver's use of static functions, these tests cannot be compiled
46  * standalone; they must be #include'd from the driver's .c file.
47  */
48 
49 
50 /** Helper macro used to snprintf to a buffer and update the buffer pointer */
51 #define	SNCATF(buffer, buflen, ...) do {				\
52 	size_t new_chars = snprintf(buffer, buflen, __VA_ARGS__);	\
53 	buffer += new_chars;						\
54 	/* be careful; snprintf's return value can be  > buflen */	\
55 	buflen -= MIN(buflen, new_chars);				\
56 } while (0)
57 
58 /* STRINGIFY and TOSTRING are used only to help turn __LINE__ into a string */
59 #define	STRINGIFY(x) #x
60 #define	TOSTRING(x) STRINGIFY(x)
61 
62 /**
63  * Writes an error message to buffer if cond is false
64  * Note the implied parameters buffer and
65  * buflen
66  */
67 #define	XNB_ASSERT(cond) ({						\
68 	int passed = (cond);						\
69 	char *_buffer = (buffer);					\
70 	size_t _buflen = (buflen);					\
71 	if (! passed) {							\
72 		strlcat(_buffer, __func__, _buflen);			\
73 		strlcat(_buffer, ":" TOSTRING(__LINE__) 		\
74 		  " Assertion Error: " #cond "\n", _buflen);		\
75 	}								\
76 	})
77 
78 
79 /**
80  * The signature used by all testcases.  If the test writes anything
81  * to buffer, then it will be considered a failure
82  * \param buffer	Return storage for error messages
83  * \param buflen	The space available in the buffer
84  */
85 typedef void testcase_t(char *buffer, size_t buflen);
86 
87 /**
88  * Signature used by setup functions
89  * \return nonzero on error
90  */
91 typedef int setup_t(void);
92 
93 typedef void teardown_t(void);
94 
95 /** A simple test fixture comprising setup, teardown, and test */
96 struct test_fixture {
97 	/** Will be run before the test to allocate and initialize variables */
98 	setup_t *setup;
99 
100 	/** Will be run if setup succeeds */
101 	testcase_t *test;
102 
103 	/** Cleans up test data whether or not the setup succeeded */
104 	teardown_t *teardown;
105 };
106 
107 typedef struct test_fixture test_fixture_t;
108 
109 static int	xnb_get1pkt(struct xnb_pkt *pkt, size_t size, uint16_t flags);
110 static int	xnb_unit_test_runner(test_fixture_t const tests[], int ntests,
111 				     char *buffer, size_t buflen);
112 
113 static int __unused
114 null_setup(void) { return 0; }
115 
116 static void __unused
117 null_teardown(void) { }
118 
119 static setup_t setup_pvt_data;
120 static teardown_t teardown_pvt_data;
121 static testcase_t xnb_ring2pkt_emptyring;
122 static testcase_t xnb_ring2pkt_1req;
123 static testcase_t xnb_ring2pkt_2req;
124 static testcase_t xnb_ring2pkt_3req;
125 static testcase_t xnb_ring2pkt_extra;
126 static testcase_t xnb_ring2pkt_partial;
127 static testcase_t xnb_ring2pkt_wraps;
128 static testcase_t xnb_txpkt2rsp_emptypkt;
129 static testcase_t xnb_txpkt2rsp_1req;
130 static testcase_t xnb_txpkt2rsp_extra;
131 static testcase_t xnb_txpkt2rsp_long;
132 static testcase_t xnb_txpkt2rsp_invalid;
133 static testcase_t xnb_txpkt2rsp_error;
134 static testcase_t xnb_txpkt2rsp_wraps;
135 static testcase_t xnb_pkt2mbufc_empty;
136 static testcase_t xnb_pkt2mbufc_short;
137 static testcase_t xnb_pkt2mbufc_csum;
138 static testcase_t xnb_pkt2mbufc_1cluster;
139 static testcase_t xnb_pkt2mbufc_largecluster;
140 static testcase_t xnb_pkt2mbufc_2cluster;
141 static testcase_t xnb_txpkt2gnttab_empty;
142 static testcase_t xnb_txpkt2gnttab_short;
143 static testcase_t xnb_txpkt2gnttab_2req;
144 static testcase_t xnb_txpkt2gnttab_2cluster;
145 static testcase_t xnb_update_mbufc_short;
146 static testcase_t xnb_update_mbufc_2req;
147 static testcase_t xnb_update_mbufc_2cluster;
148 static testcase_t xnb_mbufc2pkt_empty;
149 static testcase_t xnb_mbufc2pkt_short;
150 static testcase_t xnb_mbufc2pkt_1cluster;
151 static testcase_t xnb_mbufc2pkt_2short;
152 static testcase_t xnb_mbufc2pkt_long;
153 static testcase_t xnb_mbufc2pkt_extra;
154 static testcase_t xnb_mbufc2pkt_nospace;
155 static testcase_t xnb_rxpkt2gnttab_empty;
156 static testcase_t xnb_rxpkt2gnttab_short;
157 static testcase_t xnb_rxpkt2gnttab_2req;
158 static testcase_t xnb_rxpkt2rsp_empty;
159 static testcase_t xnb_rxpkt2rsp_short;
160 static testcase_t xnb_rxpkt2rsp_extra;
161 static testcase_t xnb_rxpkt2rsp_2short;
162 static testcase_t xnb_rxpkt2rsp_2slots;
163 static testcase_t xnb_rxpkt2rsp_copyerror;
164 static testcase_t xnb_sscanf_llu;
165 static testcase_t xnb_sscanf_lld;
166 static testcase_t xnb_sscanf_hhu;
167 static testcase_t xnb_sscanf_hhd;
168 static testcase_t xnb_sscanf_hhn;
169 
170 #if defined(INET) || defined(INET6)
171 /* TODO: add test cases for xnb_add_mbuf_cksum for IPV6 tcp and udp */
172 static testcase_t xnb_add_mbuf_cksum_arp;
173 static testcase_t xnb_add_mbuf_cksum_tcp;
174 static testcase_t xnb_add_mbuf_cksum_udp;
175 static testcase_t xnb_add_mbuf_cksum_icmp;
176 static testcase_t xnb_add_mbuf_cksum_tcp_swcksum;
177 static void	xnb_fill_eh_and_ip(struct mbuf *m, uint16_t ip_len,
178 				   uint16_t ip_id, uint16_t ip_p,
179 				   uint16_t ip_off, uint16_t ip_sum);
180 static void	xnb_fill_tcp(struct mbuf *m);
181 #endif /* INET || INET6 */
182 
183 /** Private data used by unit tests */
184 static struct {
185 	gnttab_copy_table 	gnttab;
186 	netif_rx_back_ring_t	rxb;
187 	netif_rx_front_ring_t	rxf;
188 	netif_tx_back_ring_t	txb;
189 	netif_tx_front_ring_t	txf;
190 	struct ifnet*		ifp;
191 	netif_rx_sring_t*	rxs;
192 	netif_tx_sring_t*	txs;
193 } xnb_unit_pvt;
194 
195 static inline void safe_m_freem(struct mbuf **ppMbuf) {
196 	if (*ppMbuf != NULL) {
197 		m_freem(*ppMbuf);
198 		*ppMbuf = NULL;
199 	}
200 }
201 
202 /**
203  * The unit test runner.  It will run every supplied test and return an
204  * output message as a string
205  * \param tests		An array of tests.  Every test will be attempted.
206  * \param ntests	The length of tests
207  * \param buffer	Return storage for the result string
208  * \param buflen	The length of buffer
209  * \return		The number of tests that failed
210  */
211 static int
212 xnb_unit_test_runner(test_fixture_t const tests[], int ntests, char *buffer,
213     		     size_t buflen)
214 {
215 	int i;
216 	int n_passes;
217 	int n_failures = 0;
218 
219 	for (i = 0; i < ntests; i++) {
220 		int error = tests[i].setup();
221 		if (error != 0) {
222 			SNCATF(buffer, buflen,
223 			    "Setup failed for test idx %d\n", i);
224 			n_failures++;
225 		} else {
226 			size_t new_chars;
227 
228 			tests[i].test(buffer, buflen);
229 			new_chars = strnlen(buffer, buflen);
230 			buffer += new_chars;
231 			buflen -= new_chars;
232 
233 			if (new_chars > 0) {
234 				n_failures++;
235 			}
236 		}
237 		tests[i].teardown();
238 	}
239 
240 	n_passes = ntests - n_failures;
241 	if (n_passes > 0) {
242 		SNCATF(buffer, buflen, "%d Tests Passed\n", n_passes);
243 	}
244 	if (n_failures > 0) {
245 		SNCATF(buffer, buflen, "%d Tests FAILED\n", n_failures);
246 	}
247 
248 	return n_failures;
249 }
250 
251 /** Number of unit tests.  Must match the length of the tests array below */
252 #define	TOTAL_TESTS	(53)
253 /**
254  * Max memory available for returning results.  400 chars/test should give
255  * enough space for a five line error message for every test
256  */
257 #define	TOTAL_BUFLEN	(400 * TOTAL_TESTS + 2)
258 
259 /**
260  * Called from userspace by a sysctl.  Runs all internal unit tests, and
261  * returns the results to userspace as a string
262  * \param oidp	unused
263  * \param arg1	pointer to an xnb_softc for a specific xnb device
264  * \param arg2	unused
265  * \param req	sysctl access structure
266  * \return a string via the special SYSCTL_OUT macro.
267  */
268 
269 static int
270 xnb_unit_test_main(SYSCTL_HANDLER_ARGS) {
271 	test_fixture_t const tests[TOTAL_TESTS] = {
272 		{setup_pvt_data, xnb_ring2pkt_emptyring, teardown_pvt_data},
273 		{setup_pvt_data, xnb_ring2pkt_1req, teardown_pvt_data},
274 		{setup_pvt_data, xnb_ring2pkt_2req, teardown_pvt_data},
275 		{setup_pvt_data, xnb_ring2pkt_3req, teardown_pvt_data},
276 		{setup_pvt_data, xnb_ring2pkt_extra, teardown_pvt_data},
277 		{setup_pvt_data, xnb_ring2pkt_partial, teardown_pvt_data},
278 		{setup_pvt_data, xnb_ring2pkt_wraps, teardown_pvt_data},
279 		{setup_pvt_data, xnb_txpkt2rsp_emptypkt, teardown_pvt_data},
280 		{setup_pvt_data, xnb_txpkt2rsp_1req, teardown_pvt_data},
281 		{setup_pvt_data, xnb_txpkt2rsp_extra, teardown_pvt_data},
282 		{setup_pvt_data, xnb_txpkt2rsp_long, teardown_pvt_data},
283 		{setup_pvt_data, xnb_txpkt2rsp_invalid, teardown_pvt_data},
284 		{setup_pvt_data, xnb_txpkt2rsp_error, teardown_pvt_data},
285 		{setup_pvt_data, xnb_txpkt2rsp_wraps, teardown_pvt_data},
286 		{setup_pvt_data, xnb_pkt2mbufc_empty, teardown_pvt_data},
287 		{setup_pvt_data, xnb_pkt2mbufc_short, teardown_pvt_data},
288 		{setup_pvt_data, xnb_pkt2mbufc_csum, teardown_pvt_data},
289 		{setup_pvt_data, xnb_pkt2mbufc_1cluster, teardown_pvt_data},
290 		{setup_pvt_data, xnb_pkt2mbufc_largecluster, teardown_pvt_data},
291 		{setup_pvt_data, xnb_pkt2mbufc_2cluster, teardown_pvt_data},
292 		{setup_pvt_data, xnb_txpkt2gnttab_empty, teardown_pvt_data},
293 		{setup_pvt_data, xnb_txpkt2gnttab_short, teardown_pvt_data},
294 		{setup_pvt_data, xnb_txpkt2gnttab_2req, teardown_pvt_data},
295 		{setup_pvt_data, xnb_txpkt2gnttab_2cluster, teardown_pvt_data},
296 		{setup_pvt_data, xnb_update_mbufc_short, teardown_pvt_data},
297 		{setup_pvt_data, xnb_update_mbufc_2req, teardown_pvt_data},
298 		{setup_pvt_data, xnb_update_mbufc_2cluster, teardown_pvt_data},
299 		{setup_pvt_data, xnb_mbufc2pkt_empty, teardown_pvt_data},
300 		{setup_pvt_data, xnb_mbufc2pkt_short, teardown_pvt_data},
301 		{setup_pvt_data, xnb_mbufc2pkt_1cluster, teardown_pvt_data},
302 		{setup_pvt_data, xnb_mbufc2pkt_2short, teardown_pvt_data},
303 		{setup_pvt_data, xnb_mbufc2pkt_long, teardown_pvt_data},
304 		{setup_pvt_data, xnb_mbufc2pkt_extra, teardown_pvt_data},
305 		{setup_pvt_data, xnb_mbufc2pkt_nospace, teardown_pvt_data},
306 		{setup_pvt_data, xnb_rxpkt2gnttab_empty, teardown_pvt_data},
307 		{setup_pvt_data, xnb_rxpkt2gnttab_short, teardown_pvt_data},
308 		{setup_pvt_data, xnb_rxpkt2gnttab_2req, teardown_pvt_data},
309 		{setup_pvt_data, xnb_rxpkt2rsp_empty, teardown_pvt_data},
310 		{setup_pvt_data, xnb_rxpkt2rsp_short, teardown_pvt_data},
311 		{setup_pvt_data, xnb_rxpkt2rsp_extra, teardown_pvt_data},
312 		{setup_pvt_data, xnb_rxpkt2rsp_2short, teardown_pvt_data},
313 		{setup_pvt_data, xnb_rxpkt2rsp_2slots, teardown_pvt_data},
314 		{setup_pvt_data, xnb_rxpkt2rsp_copyerror, teardown_pvt_data},
315 #if defined(INET) || defined(INET6)
316 		{null_setup, xnb_add_mbuf_cksum_arp, null_teardown},
317 		{null_setup, xnb_add_mbuf_cksum_icmp, null_teardown},
318 		{null_setup, xnb_add_mbuf_cksum_tcp, null_teardown},
319 		{null_setup, xnb_add_mbuf_cksum_tcp_swcksum, null_teardown},
320 		{null_setup, xnb_add_mbuf_cksum_udp, null_teardown},
321 #endif
322 		{null_setup, xnb_sscanf_hhd, null_teardown},
323 		{null_setup, xnb_sscanf_hhu, null_teardown},
324 		{null_setup, xnb_sscanf_lld, null_teardown},
325 		{null_setup, xnb_sscanf_llu, null_teardown},
326 		{null_setup, xnb_sscanf_hhn, null_teardown},
327 	};
328 	/**
329 	 * results is static so that the data will persist after this function
330 	 * returns.  The sysctl code expects us to return a constant string.
331 	 * \todo: the static variable is not thread safe.  Put a mutex around
332 	 * it.
333 	 */
334 	static char results[TOTAL_BUFLEN];
335 
336 	/* empty the result strings */
337 	results[0] = 0;
338 	xnb_unit_test_runner(tests, TOTAL_TESTS, results, TOTAL_BUFLEN);
339 
340 	return (SYSCTL_OUT(req, results, strnlen(results, TOTAL_BUFLEN)));
341 }
342 
343 static int
344 setup_pvt_data(void)
345 {
346 	int error = 0;
347 
348 	bzero(xnb_unit_pvt.gnttab, sizeof(xnb_unit_pvt.gnttab));
349 
350 	xnb_unit_pvt.txs = malloc(PAGE_SIZE, M_XENNETBACK, M_WAITOK|M_ZERO);
351 	if (xnb_unit_pvt.txs != NULL) {
352 		SHARED_RING_INIT(xnb_unit_pvt.txs);
353 		BACK_RING_INIT(&xnb_unit_pvt.txb, xnb_unit_pvt.txs, PAGE_SIZE);
354 		FRONT_RING_INIT(&xnb_unit_pvt.txf, xnb_unit_pvt.txs, PAGE_SIZE);
355 	} else {
356 		error = 1;
357 	}
358 
359 	xnb_unit_pvt.ifp = if_alloc(IFT_ETHER);
360 	if (xnb_unit_pvt.ifp == NULL) {
361 		error = 1;
362 	}
363 
364 	xnb_unit_pvt.rxs = malloc(PAGE_SIZE, M_XENNETBACK, M_WAITOK|M_ZERO);
365 	if (xnb_unit_pvt.rxs != NULL) {
366 		SHARED_RING_INIT(xnb_unit_pvt.rxs);
367 		BACK_RING_INIT(&xnb_unit_pvt.rxb, xnb_unit_pvt.rxs, PAGE_SIZE);
368 		FRONT_RING_INIT(&xnb_unit_pvt.rxf, xnb_unit_pvt.rxs, PAGE_SIZE);
369 	} else {
370 		error = 1;
371 	}
372 
373 	return error;
374 }
375 
376 static void
377 teardown_pvt_data(void)
378 {
379 	if (xnb_unit_pvt.txs != NULL) {
380 		free(xnb_unit_pvt.txs, M_XENNETBACK);
381 	}
382 	if (xnb_unit_pvt.rxs != NULL) {
383 		free(xnb_unit_pvt.rxs, M_XENNETBACK);
384 	}
385 	if (xnb_unit_pvt.ifp != NULL) {
386 		if_free(xnb_unit_pvt.ifp);
387 	}
388 }
389 
390 /**
391  * Verify that xnb_ring2pkt will not consume any requests from an empty ring
392  */
393 static void
394 xnb_ring2pkt_emptyring(char *buffer, size_t buflen)
395 {
396 	struct xnb_pkt pkt;
397 	int num_consumed;
398 
399 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
400 	                            xnb_unit_pvt.txb.req_cons);
401 	XNB_ASSERT(num_consumed == 0);
402 }
403 
404 /**
405  * Verify that xnb_ring2pkt can convert a single request packet correctly
406  */
407 static void
408 xnb_ring2pkt_1req(char *buffer, size_t buflen)
409 {
410 	struct xnb_pkt pkt;
411 	int num_consumed;
412 	struct netif_tx_request *req;
413 
414 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
415 	    xnb_unit_pvt.txf.req_prod_pvt);
416 
417 	req->flags = 0;
418 	req->size = 69;	/* arbitrary number for test */
419 	xnb_unit_pvt.txf.req_prod_pvt++;
420 
421 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
422 
423 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
424 	                            xnb_unit_pvt.txb.req_cons);
425 	XNB_ASSERT(num_consumed == 1);
426 	XNB_ASSERT(pkt.size == 69);
427 	XNB_ASSERT(pkt.car_size == 69);
428 	XNB_ASSERT(pkt.flags == 0);
429 	XNB_ASSERT(xnb_pkt_is_valid(&pkt));
430 	XNB_ASSERT(pkt.list_len == 1);
431 	XNB_ASSERT(pkt.car == 0);
432 }
433 
434 /**
435  * Verify that xnb_ring2pkt can convert a two request packet correctly.
436  * This tests handling of the MORE_DATA flag and cdr
437  */
438 static void
439 xnb_ring2pkt_2req(char *buffer, size_t buflen)
440 {
441 	struct xnb_pkt pkt;
442 	int num_consumed;
443 	struct netif_tx_request *req;
444 	RING_IDX start_idx = xnb_unit_pvt.txf.req_prod_pvt;
445 
446 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
447 	    xnb_unit_pvt.txf.req_prod_pvt);
448 	req->flags = NETTXF_more_data;
449 	req->size = 100;
450 	xnb_unit_pvt.txf.req_prod_pvt++;
451 
452 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
453 	    xnb_unit_pvt.txf.req_prod_pvt);
454 	req->flags = 0;
455 	req->size = 40;
456 	xnb_unit_pvt.txf.req_prod_pvt++;
457 
458 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
459 
460 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
461 	                            xnb_unit_pvt.txb.req_cons);
462 	XNB_ASSERT(num_consumed == 2);
463 	XNB_ASSERT(pkt.size == 100);
464 	XNB_ASSERT(pkt.car_size == 60);
465 	XNB_ASSERT(pkt.flags == 0);
466 	XNB_ASSERT(xnb_pkt_is_valid(&pkt));
467 	XNB_ASSERT(pkt.list_len == 2);
468 	XNB_ASSERT(pkt.car == start_idx);
469 	XNB_ASSERT(pkt.cdr == start_idx + 1);
470 }
471 
472 /**
473  * Verify that xnb_ring2pkt can convert a three request packet correctly
474  */
475 static void
476 xnb_ring2pkt_3req(char *buffer, size_t buflen)
477 {
478 	struct xnb_pkt pkt;
479 	int num_consumed;
480 	struct netif_tx_request *req;
481 	RING_IDX start_idx = xnb_unit_pvt.txf.req_prod_pvt;
482 
483 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
484 	    xnb_unit_pvt.txf.req_prod_pvt);
485 	req->flags = NETTXF_more_data;
486 	req->size = 200;
487 	xnb_unit_pvt.txf.req_prod_pvt++;
488 
489 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
490 	    xnb_unit_pvt.txf.req_prod_pvt);
491 	req->flags = NETTXF_more_data;
492 	req->size = 40;
493 	xnb_unit_pvt.txf.req_prod_pvt++;
494 
495 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
496 	    xnb_unit_pvt.txf.req_prod_pvt);
497 	req->flags = 0;
498 	req->size = 50;
499 	xnb_unit_pvt.txf.req_prod_pvt++;
500 
501 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
502 
503 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
504 	                            xnb_unit_pvt.txb.req_cons);
505 	XNB_ASSERT(num_consumed == 3);
506 	XNB_ASSERT(pkt.size == 200);
507 	XNB_ASSERT(pkt.car_size == 110);
508 	XNB_ASSERT(pkt.flags == 0);
509 	XNB_ASSERT(xnb_pkt_is_valid(&pkt));
510 	XNB_ASSERT(pkt.list_len == 3);
511 	XNB_ASSERT(pkt.car == start_idx);
512 	XNB_ASSERT(pkt.cdr == start_idx + 1);
513 	XNB_ASSERT(RING_GET_REQUEST(&xnb_unit_pvt.txb, pkt.cdr + 1) == req);
514 }
515 
516 /**
517  * Verify that xnb_ring2pkt can read extra inf
518  */
519 static void
520 xnb_ring2pkt_extra(char *buffer, size_t buflen)
521 {
522 	struct xnb_pkt pkt;
523 	int num_consumed;
524 	struct netif_tx_request *req;
525 	struct netif_extra_info *ext;
526 	RING_IDX start_idx = xnb_unit_pvt.txf.req_prod_pvt;
527 
528 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
529 	    xnb_unit_pvt.txf.req_prod_pvt);
530 	req->flags = NETTXF_extra_info | NETTXF_more_data;
531 	req->size = 150;
532 	xnb_unit_pvt.txf.req_prod_pvt++;
533 
534 	ext = (struct netif_extra_info*) RING_GET_REQUEST(&xnb_unit_pvt.txf,
535 	    xnb_unit_pvt.txf.req_prod_pvt);
536 	ext->flags = 0;
537 	ext->type = XEN_NETIF_EXTRA_TYPE_GSO;
538 	ext->u.gso.size = 250;
539 	ext->u.gso.type = XEN_NETIF_GSO_TYPE_TCPV4;
540 	ext->u.gso.features = 0;
541 	xnb_unit_pvt.txf.req_prod_pvt++;
542 
543 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
544 	    xnb_unit_pvt.txf.req_prod_pvt);
545 	req->flags = 0;
546 	req->size = 50;
547 	xnb_unit_pvt.txf.req_prod_pvt++;
548 
549 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
550 
551 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
552 	                            xnb_unit_pvt.txb.req_cons);
553 	XNB_ASSERT(num_consumed == 3);
554 	XNB_ASSERT(pkt.extra.flags == 0);
555 	XNB_ASSERT(pkt.extra.type == XEN_NETIF_EXTRA_TYPE_GSO);
556 	XNB_ASSERT(pkt.extra.u.gso.size == 250);
557 	XNB_ASSERT(pkt.extra.u.gso.type = XEN_NETIF_GSO_TYPE_TCPV4);
558 	XNB_ASSERT(pkt.size == 150);
559 	XNB_ASSERT(pkt.car_size == 100);
560 	XNB_ASSERT(pkt.flags == NETTXF_extra_info);
561 	XNB_ASSERT(xnb_pkt_is_valid(&pkt));
562 	XNB_ASSERT(pkt.list_len == 2);
563 	XNB_ASSERT(pkt.car == start_idx);
564 	XNB_ASSERT(pkt.cdr == start_idx + 2);
565 	XNB_ASSERT(RING_GET_REQUEST(&xnb_unit_pvt.txb, pkt.cdr) == req);
566 }
567 
568 /**
569  * Verify that xnb_ring2pkt will consume no requests if the entire packet is
570  * not yet in the ring
571  */
572 static void
573 xnb_ring2pkt_partial(char *buffer, size_t buflen)
574 {
575 	struct xnb_pkt pkt;
576 	int num_consumed;
577 	struct netif_tx_request *req;
578 
579 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
580 	    xnb_unit_pvt.txf.req_prod_pvt);
581 	req->flags = NETTXF_more_data;
582 	req->size = 150;
583 	xnb_unit_pvt.txf.req_prod_pvt++;
584 
585 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
586 
587 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
588 	                            xnb_unit_pvt.txb.req_cons);
589 	XNB_ASSERT(num_consumed == 0);
590 	XNB_ASSERT(! xnb_pkt_is_valid(&pkt));
591 }
592 
593 /**
594  * Verity that xnb_ring2pkt can read a packet whose requests wrap around
595  * the end of the ring
596  */
597 static void
598 xnb_ring2pkt_wraps(char *buffer, size_t buflen)
599 {
600 	struct xnb_pkt pkt;
601 	int num_consumed;
602 	struct netif_tx_request *req;
603 	unsigned int rsize;
604 
605 	/*
606 	 * Manually tweak the ring indices to create a ring with no responses
607 	 * and the next request slot at position 2 from the end
608 	 */
609 	rsize = RING_SIZE(&xnb_unit_pvt.txf);
610 	xnb_unit_pvt.txf.req_prod_pvt = rsize - 2;
611 	xnb_unit_pvt.txf.rsp_cons = rsize - 2;
612 	xnb_unit_pvt.txs->req_prod = rsize - 2;
613 	xnb_unit_pvt.txs->req_event = rsize - 1;
614 	xnb_unit_pvt.txs->rsp_prod = rsize - 2;
615 	xnb_unit_pvt.txs->rsp_event = rsize - 1;
616 	xnb_unit_pvt.txb.rsp_prod_pvt = rsize - 2;
617 	xnb_unit_pvt.txb.req_cons = rsize - 2;
618 
619 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
620 	    xnb_unit_pvt.txf.req_prod_pvt);
621 	req->flags = NETTXF_more_data;
622 	req->size = 550;
623 	xnb_unit_pvt.txf.req_prod_pvt++;
624 
625 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
626 	    xnb_unit_pvt.txf.req_prod_pvt);
627 	req->flags = NETTXF_more_data;
628 	req->size = 100;
629 	xnb_unit_pvt.txf.req_prod_pvt++;
630 
631 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
632 	    xnb_unit_pvt.txf.req_prod_pvt);
633 	req->flags = 0;
634 	req->size = 50;
635 	xnb_unit_pvt.txf.req_prod_pvt++;
636 
637 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
638 
639 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
640 	                            xnb_unit_pvt.txb.req_cons);
641 	XNB_ASSERT(num_consumed == 3);
642 	XNB_ASSERT(xnb_pkt_is_valid(&pkt));
643 	XNB_ASSERT(pkt.list_len == 3);
644 	XNB_ASSERT(RING_GET_REQUEST(&xnb_unit_pvt.txb, pkt.cdr + 1) == req);
645 }
646 
647 
648 /**
649  * xnb_txpkt2rsp should do nothing for an empty packet
650  */
651 static void
652 xnb_txpkt2rsp_emptypkt(char *buffer, size_t buflen)
653 {
654 	int num_consumed;
655 	struct xnb_pkt pkt;
656 	netif_tx_back_ring_t txb_backup = xnb_unit_pvt.txb;
657 	netif_tx_sring_t txs_backup = *xnb_unit_pvt.txs;
658 	pkt.list_len = 0;
659 
660 	/* must call xnb_ring2pkt just to intialize pkt */
661 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
662 	                            xnb_unit_pvt.txb.req_cons);
663 	xnb_txpkt2rsp(&pkt, &xnb_unit_pvt.txb, 0);
664 	XNB_ASSERT(
665 	    memcmp(&txb_backup, &xnb_unit_pvt.txb, sizeof(txb_backup)) == 0);
666 	XNB_ASSERT(
667 	    memcmp(&txs_backup, xnb_unit_pvt.txs, sizeof(txs_backup)) == 0);
668 }
669 
670 /**
671  * xnb_txpkt2rsp responding to one request
672  */
673 static void
674 xnb_txpkt2rsp_1req(char *buffer, size_t buflen)
675 {
676 	uint16_t num_consumed;
677 	struct xnb_pkt pkt;
678 	struct netif_tx_request *req;
679 	struct netif_tx_response *rsp;
680 
681 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
682 	    xnb_unit_pvt.txf.req_prod_pvt);
683 	req->size = 1000;
684 	req->flags = 0;
685 	xnb_unit_pvt.txf.req_prod_pvt++;
686 
687 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
688 
689 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
690 	                            xnb_unit_pvt.txb.req_cons);
691 	xnb_unit_pvt.txb.req_cons += num_consumed;
692 
693 	xnb_txpkt2rsp(&pkt, &xnb_unit_pvt.txb, 0);
694 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.txb, xnb_unit_pvt.txf.rsp_cons);
695 
696 	XNB_ASSERT(
697 	    xnb_unit_pvt.txb.rsp_prod_pvt == xnb_unit_pvt.txs->req_prod);
698 	XNB_ASSERT(rsp->id == req->id);
699 	XNB_ASSERT(rsp->status == NETIF_RSP_OKAY);
700 };
701 
702 /**
703  * xnb_txpkt2rsp responding to 1 data request and 1 extra info
704  */
705 static void
706 xnb_txpkt2rsp_extra(char *buffer, size_t buflen)
707 {
708 	uint16_t num_consumed;
709 	struct xnb_pkt pkt;
710 	struct netif_tx_request *req;
711 	netif_extra_info_t *ext;
712 	struct netif_tx_response *rsp;
713 
714 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
715 	    xnb_unit_pvt.txf.req_prod_pvt);
716 	req->size = 1000;
717 	req->flags = NETTXF_extra_info;
718 	req->id = 69;
719 	xnb_unit_pvt.txf.req_prod_pvt++;
720 
721 	ext = (netif_extra_info_t*) RING_GET_REQUEST(&xnb_unit_pvt.txf,
722 	    xnb_unit_pvt.txf.req_prod_pvt);
723 	ext->type = XEN_NETIF_EXTRA_TYPE_GSO;
724 	ext->flags = 0;
725 	xnb_unit_pvt.txf.req_prod_pvt++;
726 
727 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
728 
729 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
730 	                            xnb_unit_pvt.txb.req_cons);
731 	xnb_unit_pvt.txb.req_cons += num_consumed;
732 
733 	xnb_txpkt2rsp(&pkt, &xnb_unit_pvt.txb, 0);
734 
735 	XNB_ASSERT(
736 	    xnb_unit_pvt.txb.rsp_prod_pvt == xnb_unit_pvt.txs->req_prod);
737 
738 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.txb, xnb_unit_pvt.txf.rsp_cons);
739 	XNB_ASSERT(rsp->id == req->id);
740 	XNB_ASSERT(rsp->status == NETIF_RSP_OKAY);
741 
742 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.txb,
743 	    xnb_unit_pvt.txf.rsp_cons + 1);
744 	XNB_ASSERT(rsp->status == NETIF_RSP_NULL);
745 };
746 
747 /**
748  * xnb_pkg2rsp responding to 3 data requests and 1 extra info
749  */
750 static void
751 xnb_txpkt2rsp_long(char *buffer, size_t buflen)
752 {
753 	uint16_t num_consumed;
754 	struct xnb_pkt pkt;
755 	struct netif_tx_request *req;
756 	netif_extra_info_t *ext;
757 	struct netif_tx_response *rsp;
758 
759 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
760 	    xnb_unit_pvt.txf.req_prod_pvt);
761 	req->size = 1000;
762 	req->flags = NETTXF_extra_info | NETTXF_more_data;
763 	req->id = 254;
764 	xnb_unit_pvt.txf.req_prod_pvt++;
765 
766 	ext = (netif_extra_info_t*) RING_GET_REQUEST(&xnb_unit_pvt.txf,
767 	    xnb_unit_pvt.txf.req_prod_pvt);
768 	ext->type = XEN_NETIF_EXTRA_TYPE_GSO;
769 	ext->flags = 0;
770 	xnb_unit_pvt.txf.req_prod_pvt++;
771 
772 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
773 	    xnb_unit_pvt.txf.req_prod_pvt);
774 	req->size = 300;
775 	req->flags = NETTXF_more_data;
776 	req->id = 1034;
777 	xnb_unit_pvt.txf.req_prod_pvt++;
778 
779 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
780 	    xnb_unit_pvt.txf.req_prod_pvt);
781 	req->size = 400;
782 	req->flags = 0;
783 	req->id = 34;
784 	xnb_unit_pvt.txf.req_prod_pvt++;
785 
786 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
787 
788 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
789 	                            xnb_unit_pvt.txb.req_cons);
790 	xnb_unit_pvt.txb.req_cons += num_consumed;
791 
792 	xnb_txpkt2rsp(&pkt, &xnb_unit_pvt.txb, 0);
793 
794 	XNB_ASSERT(
795 	    xnb_unit_pvt.txb.rsp_prod_pvt == xnb_unit_pvt.txs->req_prod);
796 
797 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.txb, xnb_unit_pvt.txf.rsp_cons);
798 	XNB_ASSERT(rsp->id ==
799 	    RING_GET_REQUEST(&xnb_unit_pvt.txf, 0)->id);
800 	XNB_ASSERT(rsp->status == NETIF_RSP_OKAY);
801 
802 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.txb,
803 	    xnb_unit_pvt.txf.rsp_cons + 1);
804 	XNB_ASSERT(rsp->status == NETIF_RSP_NULL);
805 
806 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.txb,
807 	    xnb_unit_pvt.txf.rsp_cons + 2);
808 	XNB_ASSERT(rsp->id ==
809 	    RING_GET_REQUEST(&xnb_unit_pvt.txf, 2)->id);
810 	XNB_ASSERT(rsp->status == NETIF_RSP_OKAY);
811 
812 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.txb,
813 	    xnb_unit_pvt.txf.rsp_cons + 3);
814 	XNB_ASSERT(rsp->id ==
815 	    RING_GET_REQUEST(&xnb_unit_pvt.txf, 3)->id);
816 	XNB_ASSERT(rsp->status == NETIF_RSP_OKAY);
817 }
818 
819 /**
820  * xnb_txpkt2rsp responding to an invalid packet.
821  * Note: this test will result in an error message being printed to the console
822  * such as:
823  * xnb(xnb_ring2pkt:1306): Unknown extra info type 255.  Discarding packet
824  */
825 static void
826 xnb_txpkt2rsp_invalid(char *buffer, size_t buflen)
827 {
828 	uint16_t num_consumed;
829 	struct xnb_pkt pkt;
830 	struct netif_tx_request *req;
831 	netif_extra_info_t *ext;
832 	struct netif_tx_response *rsp;
833 
834 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
835 	    xnb_unit_pvt.txf.req_prod_pvt);
836 	req->size = 1000;
837 	req->flags = NETTXF_extra_info;
838 	req->id = 69;
839 	xnb_unit_pvt.txf.req_prod_pvt++;
840 
841 	ext = (netif_extra_info_t*) RING_GET_REQUEST(&xnb_unit_pvt.txf,
842 	    xnb_unit_pvt.txf.req_prod_pvt);
843 	ext->type = 0xFF;	/* Invalid extra type */
844 	ext->flags = 0;
845 	xnb_unit_pvt.txf.req_prod_pvt++;
846 
847 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
848 
849 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
850 	                            xnb_unit_pvt.txb.req_cons);
851 	xnb_unit_pvt.txb.req_cons += num_consumed;
852 	XNB_ASSERT(! xnb_pkt_is_valid(&pkt));
853 
854 	xnb_txpkt2rsp(&pkt, &xnb_unit_pvt.txb, 0);
855 
856 	XNB_ASSERT(
857 	    xnb_unit_pvt.txb.rsp_prod_pvt == xnb_unit_pvt.txs->req_prod);
858 
859 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.txb, xnb_unit_pvt.txf.rsp_cons);
860 	XNB_ASSERT(rsp->id == req->id);
861 	XNB_ASSERT(rsp->status == NETIF_RSP_ERROR);
862 
863 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.txb,
864 	    xnb_unit_pvt.txf.rsp_cons + 1);
865 	XNB_ASSERT(rsp->status == NETIF_RSP_NULL);
866 };
867 
868 /**
869  * xnb_txpkt2rsp responding to one request which caused an error
870  */
871 static void
872 xnb_txpkt2rsp_error(char *buffer, size_t buflen)
873 {
874 	uint16_t num_consumed;
875 	struct xnb_pkt pkt;
876 	struct netif_tx_request *req;
877 	struct netif_tx_response *rsp;
878 
879 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
880 	    xnb_unit_pvt.txf.req_prod_pvt);
881 	req->size = 1000;
882 	req->flags = 0;
883 	xnb_unit_pvt.txf.req_prod_pvt++;
884 
885 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
886 
887 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
888 	                            xnb_unit_pvt.txb.req_cons);
889 	xnb_unit_pvt.txb.req_cons += num_consumed;
890 
891 	xnb_txpkt2rsp(&pkt, &xnb_unit_pvt.txb, 1);
892 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.txb, xnb_unit_pvt.txf.rsp_cons);
893 
894 	XNB_ASSERT(
895 	    xnb_unit_pvt.txb.rsp_prod_pvt == xnb_unit_pvt.txs->req_prod);
896 	XNB_ASSERT(rsp->id == req->id);
897 	XNB_ASSERT(rsp->status == NETIF_RSP_ERROR);
898 };
899 
900 /**
901  * xnb_txpkt2rsp's responses wrap around the end of the ring
902  */
903 static void
904 xnb_txpkt2rsp_wraps(char *buffer, size_t buflen)
905 {
906 	struct xnb_pkt pkt;
907 	int num_consumed;
908 	struct netif_tx_request *req;
909 	struct netif_tx_response *rsp;
910 	unsigned int rsize;
911 
912 	/*
913 	 * Manually tweak the ring indices to create a ring with no responses
914 	 * and the next request slot at position 2 from the end
915 	 */
916 	rsize = RING_SIZE(&xnb_unit_pvt.txf);
917 	xnb_unit_pvt.txf.req_prod_pvt = rsize - 2;
918 	xnb_unit_pvt.txf.rsp_cons = rsize - 2;
919 	xnb_unit_pvt.txs->req_prod = rsize - 2;
920 	xnb_unit_pvt.txs->req_event = rsize - 1;
921 	xnb_unit_pvt.txs->rsp_prod = rsize - 2;
922 	xnb_unit_pvt.txs->rsp_event = rsize - 1;
923 	xnb_unit_pvt.txb.rsp_prod_pvt = rsize - 2;
924 	xnb_unit_pvt.txb.req_cons = rsize - 2;
925 
926 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
927 	    xnb_unit_pvt.txf.req_prod_pvt);
928 	req->flags = NETTXF_more_data;
929 	req->size = 550;
930 	req->id = 1;
931 	xnb_unit_pvt.txf.req_prod_pvt++;
932 
933 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
934 	    xnb_unit_pvt.txf.req_prod_pvt);
935 	req->flags = NETTXF_more_data;
936 	req->size = 100;
937 	req->id = 2;
938 	xnb_unit_pvt.txf.req_prod_pvt++;
939 
940 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
941 	    xnb_unit_pvt.txf.req_prod_pvt);
942 	req->flags = 0;
943 	req->size = 50;
944 	req->id = 3;
945 	xnb_unit_pvt.txf.req_prod_pvt++;
946 
947 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
948 
949 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
950 	                            xnb_unit_pvt.txb.req_cons);
951 
952 	xnb_txpkt2rsp(&pkt, &xnb_unit_pvt.txb, 0);
953 
954 	XNB_ASSERT(
955 	    xnb_unit_pvt.txb.rsp_prod_pvt == xnb_unit_pvt.txs->req_prod);
956 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.txb,
957 	    xnb_unit_pvt.txf.rsp_cons + 2);
958 	XNB_ASSERT(rsp->id == req->id);
959 	XNB_ASSERT(rsp->status == NETIF_RSP_OKAY);
960 }
961 
962 
963 /**
964  * Helper function used to setup pkt2mbufc tests
965  * \param size     size in bytes of the single request to push to the ring
966  * \param flags		optional flags to put in the netif request
967  * \param[out] pkt the returned packet object
968  * \return number of requests consumed from the ring
969  */
970 static int
971 xnb_get1pkt(struct xnb_pkt *pkt, size_t size, uint16_t flags)
972 {
973 	struct netif_tx_request *req;
974 
975 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
976 	    xnb_unit_pvt.txf.req_prod_pvt);
977 	req->flags = flags;
978 	req->size = size;
979 	xnb_unit_pvt.txf.req_prod_pvt++;
980 
981 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
982 
983 	return xnb_ring2pkt(pkt, &xnb_unit_pvt.txb,
984 	                            xnb_unit_pvt.txb.req_cons);
985 }
986 
987 /**
988  * xnb_pkt2mbufc on an empty packet
989  */
990 static void
991 xnb_pkt2mbufc_empty(char *buffer, size_t buflen)
992 {
993 	int num_consumed;
994 	struct xnb_pkt pkt;
995 	struct mbuf *pMbuf;
996 	pkt.list_len = 0;
997 
998 	/* must call xnb_ring2pkt just to intialize pkt */
999 	num_consumed = xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb,
1000 	                            xnb_unit_pvt.txb.req_cons);
1001 	pkt.size = 0;
1002 	pMbuf = xnb_pkt2mbufc(&pkt, xnb_unit_pvt.ifp);
1003 	safe_m_freem(&pMbuf);
1004 }
1005 
1006 /**
1007  * xnb_pkt2mbufc on short packet that can fit in an mbuf internal buffer
1008  */
1009 static void
1010 xnb_pkt2mbufc_short(char *buffer, size_t buflen)
1011 {
1012 	const size_t size = MINCLSIZE - 1;
1013 	struct xnb_pkt pkt;
1014 	struct mbuf *pMbuf;
1015 
1016 	xnb_get1pkt(&pkt, size, 0);
1017 
1018 	pMbuf = xnb_pkt2mbufc(&pkt, xnb_unit_pvt.ifp);
1019 	XNB_ASSERT(M_TRAILINGSPACE(pMbuf) >= size);
1020 	safe_m_freem(&pMbuf);
1021 }
1022 
1023 /**
1024  * xnb_pkt2mbufc on short packet whose checksum was validated by the netfron
1025  */
1026 static void
1027 xnb_pkt2mbufc_csum(char *buffer, size_t buflen)
1028 {
1029 	const size_t size = MINCLSIZE - 1;
1030 	struct xnb_pkt pkt;
1031 	struct mbuf *pMbuf;
1032 
1033 	xnb_get1pkt(&pkt, size, NETTXF_data_validated);
1034 
1035 	pMbuf = xnb_pkt2mbufc(&pkt, xnb_unit_pvt.ifp);
1036 	XNB_ASSERT(M_TRAILINGSPACE(pMbuf) >= size);
1037 	XNB_ASSERT(pMbuf->m_pkthdr.csum_flags & CSUM_IP_CHECKED);
1038 	XNB_ASSERT(pMbuf->m_pkthdr.csum_flags & CSUM_IP_VALID);
1039 	XNB_ASSERT(pMbuf->m_pkthdr.csum_flags & CSUM_DATA_VALID);
1040 	XNB_ASSERT(pMbuf->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR);
1041 	safe_m_freem(&pMbuf);
1042 }
1043 
1044 /**
1045  * xnb_pkt2mbufc on packet that can fit in one cluster
1046  */
1047 static void
1048 xnb_pkt2mbufc_1cluster(char *buffer, size_t buflen)
1049 {
1050 	const size_t size = MINCLSIZE;
1051 	struct xnb_pkt pkt;
1052 	struct mbuf *pMbuf;
1053 
1054 	xnb_get1pkt(&pkt, size, 0);
1055 
1056 	pMbuf = xnb_pkt2mbufc(&pkt, xnb_unit_pvt.ifp);
1057 	XNB_ASSERT(M_TRAILINGSPACE(pMbuf) >= size);
1058 	safe_m_freem(&pMbuf);
1059 }
1060 
1061 /**
1062  * xnb_pkt2mbufc on packet that cannot fit in one regular cluster
1063  */
1064 static void
1065 xnb_pkt2mbufc_largecluster(char *buffer, size_t buflen)
1066 {
1067 	const size_t size = MCLBYTES + 1;
1068 	struct xnb_pkt pkt;
1069 	struct mbuf *pMbuf;
1070 
1071 	xnb_get1pkt(&pkt, size, 0);
1072 
1073 	pMbuf = xnb_pkt2mbufc(&pkt, xnb_unit_pvt.ifp);
1074 	XNB_ASSERT(M_TRAILINGSPACE(pMbuf) >= size);
1075 	safe_m_freem(&pMbuf);
1076 }
1077 
1078 /**
1079  * xnb_pkt2mbufc on packet that cannot fit in one clusters
1080  */
1081 static void
1082 xnb_pkt2mbufc_2cluster(char *buffer, size_t buflen)
1083 {
1084 	const size_t size = 2 * MCLBYTES + 1;
1085 	size_t space = 0;
1086 	struct xnb_pkt pkt;
1087 	struct mbuf *pMbuf;
1088 	struct mbuf *m;
1089 
1090 	xnb_get1pkt(&pkt, size, 0);
1091 
1092 	pMbuf = xnb_pkt2mbufc(&pkt, xnb_unit_pvt.ifp);
1093 
1094 	for (m = pMbuf; m != NULL; m = m->m_next) {
1095 		space += M_TRAILINGSPACE(m);
1096 	}
1097 	XNB_ASSERT(space >= size);
1098 	safe_m_freem(&pMbuf);
1099 }
1100 
1101 /**
1102  * xnb_txpkt2gnttab on an empty packet.  Should return empty gnttab
1103  */
1104 static void
1105 xnb_txpkt2gnttab_empty(char *buffer, size_t buflen)
1106 {
1107 	int n_entries;
1108 	struct xnb_pkt pkt;
1109 	struct mbuf *pMbuf;
1110 	pkt.list_len = 0;
1111 
1112 	/* must call xnb_ring2pkt just to intialize pkt */
1113 	xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb, xnb_unit_pvt.txb.req_cons);
1114 	pkt.size = 0;
1115 	pMbuf = xnb_pkt2mbufc(&pkt, xnb_unit_pvt.ifp);
1116 	n_entries = xnb_txpkt2gnttab(&pkt, pMbuf, xnb_unit_pvt.gnttab,
1117 	    &xnb_unit_pvt.txb, DOMID_FIRST_RESERVED);
1118 	XNB_ASSERT(n_entries == 0);
1119 	safe_m_freem(&pMbuf);
1120 }
1121 
1122 /**
1123  * xnb_txpkt2gnttab on a short packet, that can fit in one mbuf internal buffer
1124  * and has one request
1125  */
1126 static void
1127 xnb_txpkt2gnttab_short(char *buffer, size_t buflen)
1128 {
1129 	const size_t size = MINCLSIZE - 1;
1130 	int n_entries;
1131 	struct xnb_pkt pkt;
1132 	struct mbuf *pMbuf;
1133 
1134 	struct netif_tx_request *req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
1135 	    xnb_unit_pvt.txf.req_prod_pvt);
1136 	req->flags = 0;
1137 	req->size = size;
1138 	req->gref = 7;
1139 	req->offset = 17;
1140 	xnb_unit_pvt.txf.req_prod_pvt++;
1141 
1142 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
1143 
1144 	xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb, xnb_unit_pvt.txb.req_cons);
1145 
1146 	pMbuf = xnb_pkt2mbufc(&pkt, xnb_unit_pvt.ifp);
1147 	n_entries = xnb_txpkt2gnttab(&pkt, pMbuf, xnb_unit_pvt.gnttab,
1148 	    &xnb_unit_pvt.txb, DOMID_FIRST_RESERVED);
1149 	XNB_ASSERT(n_entries == 1);
1150 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].len == size);
1151 	/* flags should indicate gref's for source */
1152 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].flags & GNTCOPY_source_gref);
1153 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].source.offset == req->offset);
1154 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].source.domid == DOMID_SELF);
1155 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].dest.offset == virt_to_offset(
1156 	      mtod(pMbuf, vm_offset_t)));
1157 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].dest.u.gmfn ==
1158 		virt_to_mfn(mtod(pMbuf, vm_offset_t)));
1159 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].dest.domid == DOMID_FIRST_RESERVED);
1160 	safe_m_freem(&pMbuf);
1161 }
1162 
1163 /**
1164  * xnb_txpkt2gnttab on a packet with two requests, that can fit into a single
1165  * mbuf cluster
1166  */
1167 static void
1168 xnb_txpkt2gnttab_2req(char *buffer, size_t buflen)
1169 {
1170 	int n_entries;
1171 	struct xnb_pkt pkt;
1172 	struct mbuf *pMbuf;
1173 
1174 	struct netif_tx_request *req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
1175 	    xnb_unit_pvt.txf.req_prod_pvt);
1176 	req->flags = NETTXF_more_data;
1177 	req->size = 1900;
1178 	req->gref = 7;
1179 	req->offset = 0;
1180 	xnb_unit_pvt.txf.req_prod_pvt++;
1181 
1182 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
1183 	    xnb_unit_pvt.txf.req_prod_pvt);
1184 	req->flags = 0;
1185 	req->size = 500;
1186 	req->gref = 8;
1187 	req->offset = 0;
1188 	xnb_unit_pvt.txf.req_prod_pvt++;
1189 
1190 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
1191 
1192 	xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb, xnb_unit_pvt.txb.req_cons);
1193 
1194 	pMbuf = xnb_pkt2mbufc(&pkt, xnb_unit_pvt.ifp);
1195 	n_entries = xnb_txpkt2gnttab(&pkt, pMbuf, xnb_unit_pvt.gnttab,
1196 	    &xnb_unit_pvt.txb, DOMID_FIRST_RESERVED);
1197 
1198 	XNB_ASSERT(n_entries == 2);
1199 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].len == 1400);
1200 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].dest.offset == virt_to_offset(
1201 	      mtod(pMbuf, vm_offset_t)));
1202 
1203 	XNB_ASSERT(xnb_unit_pvt.gnttab[1].len == 500);
1204 	XNB_ASSERT(xnb_unit_pvt.gnttab[1].dest.offset == virt_to_offset(
1205 	      mtod(pMbuf, vm_offset_t) + 1400));
1206 	safe_m_freem(&pMbuf);
1207 }
1208 
1209 /**
1210  * xnb_txpkt2gnttab on a single request that spans two mbuf clusters
1211  */
1212 static void
1213 xnb_txpkt2gnttab_2cluster(char *buffer, size_t buflen)
1214 {
1215 	int n_entries;
1216 	struct xnb_pkt pkt;
1217 	struct mbuf *pMbuf;
1218 	const uint16_t data_this_transaction = (MCLBYTES*2) + 1;
1219 
1220 	struct netif_tx_request *req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
1221 	    xnb_unit_pvt.txf.req_prod_pvt);
1222 	req->flags = 0;
1223 	req->size = data_this_transaction;
1224 	req->gref = 8;
1225 	req->offset = 0;
1226 	xnb_unit_pvt.txf.req_prod_pvt++;
1227 
1228 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
1229 	xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb, xnb_unit_pvt.txb.req_cons);
1230 
1231 	pMbuf = xnb_pkt2mbufc(&pkt, xnb_unit_pvt.ifp);
1232 	XNB_ASSERT(pMbuf != NULL);
1233 	if (pMbuf == NULL)
1234 		return;
1235 
1236 	n_entries = xnb_txpkt2gnttab(&pkt, pMbuf, xnb_unit_pvt.gnttab,
1237 	    &xnb_unit_pvt.txb, DOMID_FIRST_RESERVED);
1238 
1239 	if (M_TRAILINGSPACE(pMbuf) == MCLBYTES) {
1240 		/* there should be three mbufs and three gnttab entries */
1241 		XNB_ASSERT(n_entries == 3);
1242 		XNB_ASSERT(xnb_unit_pvt.gnttab[0].len == MCLBYTES);
1243 		XNB_ASSERT(
1244 		    xnb_unit_pvt.gnttab[0].dest.offset == virt_to_offset(
1245 		      mtod(pMbuf, vm_offset_t)));
1246 		XNB_ASSERT(xnb_unit_pvt.gnttab[0].source.offset == 0);
1247 
1248 		XNB_ASSERT(xnb_unit_pvt.gnttab[1].len == MCLBYTES);
1249 		XNB_ASSERT(
1250 		    xnb_unit_pvt.gnttab[1].dest.offset == virt_to_offset(
1251 		      mtod(pMbuf->m_next, vm_offset_t)));
1252 		XNB_ASSERT(xnb_unit_pvt.gnttab[1].source.offset == MCLBYTES);
1253 
1254 		XNB_ASSERT(xnb_unit_pvt.gnttab[2].len == 1);
1255 		XNB_ASSERT(
1256 		    xnb_unit_pvt.gnttab[2].dest.offset == virt_to_offset(
1257 		      mtod(pMbuf->m_next, vm_offset_t)));
1258 		XNB_ASSERT(xnb_unit_pvt.gnttab[2].source.offset == 2 *
1259 			    MCLBYTES);
1260 	} else if (M_TRAILINGSPACE(pMbuf) == 2 * MCLBYTES) {
1261 		/* there should be two mbufs and two gnttab entries */
1262 		XNB_ASSERT(n_entries == 2);
1263 		XNB_ASSERT(xnb_unit_pvt.gnttab[0].len == 2 * MCLBYTES);
1264 		XNB_ASSERT(
1265 		    xnb_unit_pvt.gnttab[0].dest.offset == virt_to_offset(
1266 		      mtod(pMbuf, vm_offset_t)));
1267 		XNB_ASSERT(xnb_unit_pvt.gnttab[0].source.offset == 0);
1268 
1269 		XNB_ASSERT(xnb_unit_pvt.gnttab[1].len == 1);
1270 		XNB_ASSERT(
1271 		    xnb_unit_pvt.gnttab[1].dest.offset == virt_to_offset(
1272 		      mtod(pMbuf->m_next, vm_offset_t)));
1273 		XNB_ASSERT(
1274 		    xnb_unit_pvt.gnttab[1].source.offset == 2 * MCLBYTES);
1275 
1276 	} else {
1277 		/* should never get here */
1278 		XNB_ASSERT(0);
1279 	}
1280 	m_freem(pMbuf);
1281 }
1282 
1283 
1284 /**
1285  * xnb_update_mbufc on a short packet that only has one gnttab entry
1286  */
1287 static void
1288 xnb_update_mbufc_short(char *buffer, size_t buflen)
1289 {
1290 	const size_t size = MINCLSIZE - 1;
1291 	int n_entries;
1292 	struct xnb_pkt pkt;
1293 	struct mbuf *pMbuf;
1294 
1295 	struct netif_tx_request *req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
1296 	    xnb_unit_pvt.txf.req_prod_pvt);
1297 	req->flags = 0;
1298 	req->size = size;
1299 	req->gref = 7;
1300 	req->offset = 17;
1301 	xnb_unit_pvt.txf.req_prod_pvt++;
1302 
1303 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
1304 
1305 	xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb, xnb_unit_pvt.txb.req_cons);
1306 
1307 	pMbuf = xnb_pkt2mbufc(&pkt, xnb_unit_pvt.ifp);
1308 	n_entries = xnb_txpkt2gnttab(&pkt, pMbuf, xnb_unit_pvt.gnttab,
1309 	    &xnb_unit_pvt.txb, DOMID_FIRST_RESERVED);
1310 
1311 	/* Update grant table's status fields as the hypervisor call would */
1312 	xnb_unit_pvt.gnttab[0].status = GNTST_okay;
1313 
1314 	xnb_update_mbufc(pMbuf, xnb_unit_pvt.gnttab, n_entries);
1315 	XNB_ASSERT(pMbuf->m_len == size);
1316 	XNB_ASSERT(pMbuf->m_pkthdr.len == size);
1317 	safe_m_freem(&pMbuf);
1318 }
1319 
1320 /**
1321  * xnb_update_mbufc on a packet with two requests, that can fit into a single
1322  * mbuf cluster
1323  */
1324 static void
1325 xnb_update_mbufc_2req(char *buffer, size_t buflen)
1326 {
1327 	int n_entries;
1328 	struct xnb_pkt pkt;
1329 	struct mbuf *pMbuf;
1330 
1331 	struct netif_tx_request *req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
1332 	    xnb_unit_pvt.txf.req_prod_pvt);
1333 	req->flags = NETTXF_more_data;
1334 	req->size = 1900;
1335 	req->gref = 7;
1336 	req->offset = 0;
1337 	xnb_unit_pvt.txf.req_prod_pvt++;
1338 
1339 	req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
1340 	    xnb_unit_pvt.txf.req_prod_pvt);
1341 	req->flags = 0;
1342 	req->size = 500;
1343 	req->gref = 8;
1344 	req->offset = 0;
1345 	xnb_unit_pvt.txf.req_prod_pvt++;
1346 
1347 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
1348 
1349 	xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb, xnb_unit_pvt.txb.req_cons);
1350 
1351 	pMbuf = xnb_pkt2mbufc(&pkt, xnb_unit_pvt.ifp);
1352 	n_entries = xnb_txpkt2gnttab(&pkt, pMbuf, xnb_unit_pvt.gnttab,
1353 	    &xnb_unit_pvt.txb, DOMID_FIRST_RESERVED);
1354 
1355 	/* Update grant table's status fields as the hypervisor call would */
1356 	xnb_unit_pvt.gnttab[0].status = GNTST_okay;
1357 	xnb_unit_pvt.gnttab[1].status = GNTST_okay;
1358 
1359 	xnb_update_mbufc(pMbuf, xnb_unit_pvt.gnttab, n_entries);
1360 	XNB_ASSERT(n_entries == 2);
1361 	XNB_ASSERT(pMbuf->m_pkthdr.len == 1900);
1362 	XNB_ASSERT(pMbuf->m_len == 1900);
1363 
1364 	safe_m_freem(&pMbuf);
1365 }
1366 
1367 /**
1368  * xnb_update_mbufc on a single request that spans two mbuf clusters
1369  */
1370 static void
1371 xnb_update_mbufc_2cluster(char *buffer, size_t buflen)
1372 {
1373 	int i;
1374 	int n_entries;
1375 	struct xnb_pkt pkt;
1376 	struct mbuf *pMbuf;
1377 	const uint16_t data_this_transaction = (MCLBYTES*2) + 1;
1378 
1379 	struct netif_tx_request *req = RING_GET_REQUEST(&xnb_unit_pvt.txf,
1380 	    xnb_unit_pvt.txf.req_prod_pvt);
1381 	req->flags = 0;
1382 	req->size = data_this_transaction;
1383 	req->gref = 8;
1384 	req->offset = 0;
1385 	xnb_unit_pvt.txf.req_prod_pvt++;
1386 
1387 	RING_PUSH_REQUESTS(&xnb_unit_pvt.txf);
1388 	xnb_ring2pkt(&pkt, &xnb_unit_pvt.txb, xnb_unit_pvt.txb.req_cons);
1389 
1390 	pMbuf = xnb_pkt2mbufc(&pkt, xnb_unit_pvt.ifp);
1391 	n_entries = xnb_txpkt2gnttab(&pkt, pMbuf, xnb_unit_pvt.gnttab,
1392 	    &xnb_unit_pvt.txb, DOMID_FIRST_RESERVED);
1393 
1394 	/* Update grant table's status fields */
1395 	for (i = 0; i < n_entries; i++) {
1396 		xnb_unit_pvt.gnttab[0].status = GNTST_okay;
1397 	}
1398 	xnb_update_mbufc(pMbuf, xnb_unit_pvt.gnttab, n_entries);
1399 
1400 	if (n_entries == 3) {
1401 		/* there should be three mbufs and three gnttab entries */
1402 		XNB_ASSERT(pMbuf->m_pkthdr.len == data_this_transaction);
1403 		XNB_ASSERT(pMbuf->m_len == MCLBYTES);
1404 		XNB_ASSERT(pMbuf->m_next->m_len == MCLBYTES);
1405 		XNB_ASSERT(pMbuf->m_next->m_next->m_len == 1);
1406 	} else if (n_entries == 2) {
1407 		/* there should be two mbufs and two gnttab entries */
1408 		XNB_ASSERT(n_entries == 2);
1409 		XNB_ASSERT(pMbuf->m_pkthdr.len == data_this_transaction);
1410 		XNB_ASSERT(pMbuf->m_len == 2 * MCLBYTES);
1411 		XNB_ASSERT(pMbuf->m_next->m_len == 1);
1412 	} else {
1413 		/* should never get here */
1414 		XNB_ASSERT(0);
1415 	}
1416 	safe_m_freem(&pMbuf);
1417 }
1418 
1419 /** xnb_mbufc2pkt on an empty mbufc */
1420 static void
1421 xnb_mbufc2pkt_empty(char *buffer, size_t buflen) {
1422 	struct xnb_pkt pkt;
1423 	int free_slots = 64;
1424 	struct mbuf *mbuf;
1425 
1426 	mbuf = m_get(M_WAITOK, MT_DATA);
1427 	/*
1428 	 * note: it is illegal to set M_PKTHDR on a mbuf with no data.  Doing so
1429 	 * will cause m_freem to segfault
1430 	 */
1431 	XNB_ASSERT(mbuf->m_len == 0);
1432 
1433 	xnb_mbufc2pkt(mbuf, &pkt, 0, free_slots);
1434 	XNB_ASSERT(! xnb_pkt_is_valid(&pkt));
1435 
1436 	safe_m_freem(&mbuf);
1437 }
1438 
1439 /** xnb_mbufc2pkt on a short mbufc */
1440 static void
1441 xnb_mbufc2pkt_short(char *buffer, size_t buflen) {
1442 	struct xnb_pkt pkt;
1443 	size_t size = 128;
1444 	int free_slots = 64;
1445 	RING_IDX start = 9;
1446 	struct mbuf *mbuf;
1447 
1448 	mbuf = m_getm(NULL, size, M_WAITOK, MT_DATA);
1449 	mbuf->m_flags |= M_PKTHDR;
1450 	mbuf->m_pkthdr.len = size;
1451 	mbuf->m_len = size;
1452 
1453 	xnb_mbufc2pkt(mbuf, &pkt, start, free_slots);
1454 	XNB_ASSERT(xnb_pkt_is_valid(&pkt));
1455 	XNB_ASSERT(pkt.size == size);
1456 	XNB_ASSERT(pkt.car_size == size);
1457 	XNB_ASSERT(! (pkt.flags &
1458 	      (NETRXF_more_data | NETRXF_extra_info)));
1459 	XNB_ASSERT(pkt.list_len == 1);
1460 	XNB_ASSERT(pkt.car == start);
1461 
1462 	safe_m_freem(&mbuf);
1463 }
1464 
1465 /** xnb_mbufc2pkt on a single mbuf with an mbuf cluster */
1466 static void
1467 xnb_mbufc2pkt_1cluster(char *buffer, size_t buflen) {
1468 	struct xnb_pkt pkt;
1469 	size_t size = MCLBYTES;
1470 	int free_slots = 32;
1471 	RING_IDX start = 12;
1472 	struct mbuf *mbuf;
1473 
1474 	mbuf = m_getm(NULL, size, M_WAITOK, MT_DATA);
1475 	mbuf->m_flags |= M_PKTHDR;
1476 	mbuf->m_pkthdr.len = size;
1477 	mbuf->m_len = size;
1478 
1479 	xnb_mbufc2pkt(mbuf, &pkt, start, free_slots);
1480 	XNB_ASSERT(xnb_pkt_is_valid(&pkt));
1481 	XNB_ASSERT(pkt.size == size);
1482 	XNB_ASSERT(pkt.car_size == size);
1483 	XNB_ASSERT(! (pkt.flags &
1484 	      (NETRXF_more_data | NETRXF_extra_info)));
1485 	XNB_ASSERT(pkt.list_len == 1);
1486 	XNB_ASSERT(pkt.car == start);
1487 
1488 	safe_m_freem(&mbuf);
1489 }
1490 
1491 /** xnb_mbufc2pkt on a two-mbuf chain with short data regions */
1492 static void
1493 xnb_mbufc2pkt_2short(char *buffer, size_t buflen) {
1494 	struct xnb_pkt pkt;
1495 	size_t size1 = MHLEN - 5;
1496 	size_t size2 = MHLEN - 15;
1497 	int free_slots = 32;
1498 	RING_IDX start = 14;
1499 	struct mbuf *mbufc, *mbufc2;
1500 
1501 	mbufc = m_getm(NULL, size1, M_WAITOK, MT_DATA);
1502 	XNB_ASSERT(mbufc != NULL);
1503 	if (mbufc == NULL)
1504 		return;
1505 	mbufc->m_flags |= M_PKTHDR;
1506 
1507 	mbufc2 = m_getm(mbufc, size2, M_WAITOK, MT_DATA);
1508 	XNB_ASSERT(mbufc2 != NULL);
1509 	if (mbufc2 == NULL) {
1510 		safe_m_freem(&mbufc);
1511 		return;
1512 	}
1513 	mbufc2->m_pkthdr.len = size1 + size2;
1514 	mbufc2->m_len = size1;
1515 
1516 	xnb_mbufc2pkt(mbufc2, &pkt, start, free_slots);
1517 	XNB_ASSERT(xnb_pkt_is_valid(&pkt));
1518 	XNB_ASSERT(pkt.size == size1 + size2);
1519 	XNB_ASSERT(pkt.car == start);
1520 	/*
1521 	 * The second m_getm may allocate a new mbuf and append
1522 	 * it to the chain, or it may simply extend the first mbuf.
1523 	 */
1524 	if (mbufc2->m_next != NULL) {
1525 		XNB_ASSERT(pkt.car_size == size1);
1526 		XNB_ASSERT(pkt.list_len == 1);
1527 		XNB_ASSERT(pkt.cdr == start + 1);
1528 	}
1529 
1530 	safe_m_freem(&mbufc2);
1531 }
1532 
1533 /** xnb_mbufc2pkt on a mbuf chain with >1 mbuf cluster */
1534 static void
1535 xnb_mbufc2pkt_long(char *buffer, size_t buflen) {
1536 	struct xnb_pkt pkt;
1537 	size_t size = 14 * MCLBYTES / 3;
1538 	size_t size_remaining;
1539 	int free_slots = 15;
1540 	RING_IDX start = 3;
1541 	struct mbuf *mbufc, *m;
1542 
1543 	mbufc = m_getm(NULL, size, M_WAITOK, MT_DATA);
1544 	XNB_ASSERT(mbufc != NULL);
1545 	if (mbufc == NULL)
1546 		return;
1547 	mbufc->m_flags |= M_PKTHDR;
1548 
1549 	mbufc->m_pkthdr.len = size;
1550 	size_remaining = size;
1551 	for (m = mbufc; m != NULL; m = m->m_next) {
1552 		m->m_len = MAX(M_TRAILINGSPACE(m), size_remaining);
1553 		size_remaining -= m->m_len;
1554 	}
1555 
1556 	xnb_mbufc2pkt(mbufc, &pkt, start, free_slots);
1557 	XNB_ASSERT(xnb_pkt_is_valid(&pkt));
1558 	XNB_ASSERT(pkt.size == size);
1559 	XNB_ASSERT(pkt.car == start);
1560 	XNB_ASSERT(pkt.car_size = mbufc->m_len);
1561 	/*
1562 	 * There should be >1 response in the packet, and there is no
1563 	 * extra info.
1564 	 */
1565 	XNB_ASSERT(! (pkt.flags & NETRXF_extra_info));
1566 	XNB_ASSERT(pkt.cdr == pkt.car + 1);
1567 
1568 	safe_m_freem(&mbufc);
1569 }
1570 
1571 /** xnb_mbufc2pkt on a mbuf chain with >1 mbuf cluster and extra info */
1572 static void
1573 xnb_mbufc2pkt_extra(char *buffer, size_t buflen) {
1574 	struct xnb_pkt pkt;
1575 	size_t size = 14 * MCLBYTES / 3;
1576 	size_t size_remaining;
1577 	int free_slots = 15;
1578 	RING_IDX start = 3;
1579 	struct mbuf *mbufc, *m;
1580 
1581 	mbufc = m_getm(NULL, size, M_WAITOK, MT_DATA);
1582 	XNB_ASSERT(mbufc != NULL);
1583 	if (mbufc == NULL)
1584 		return;
1585 
1586 	mbufc->m_flags |= M_PKTHDR;
1587 	mbufc->m_pkthdr.len = size;
1588 	mbufc->m_pkthdr.csum_flags |= CSUM_TSO;
1589 	mbufc->m_pkthdr.tso_segsz = TCP_MSS - 40;
1590 	size_remaining = size;
1591 	for (m = mbufc; m != NULL; m = m->m_next) {
1592 		m->m_len = MAX(M_TRAILINGSPACE(m), size_remaining);
1593 		size_remaining -= m->m_len;
1594 	}
1595 
1596 	xnb_mbufc2pkt(mbufc, &pkt, start, free_slots);
1597 	XNB_ASSERT(xnb_pkt_is_valid(&pkt));
1598 	XNB_ASSERT(pkt.size == size);
1599 	XNB_ASSERT(pkt.car == start);
1600 	XNB_ASSERT(pkt.car_size = mbufc->m_len);
1601 	/* There should be >1 response in the packet, there is extra info */
1602 	XNB_ASSERT(pkt.flags & NETRXF_extra_info);
1603 	XNB_ASSERT(pkt.flags & NETRXF_data_validated);
1604 	XNB_ASSERT(pkt.cdr == pkt.car + 2);
1605 	XNB_ASSERT(pkt.extra.u.gso.size = mbufc->m_pkthdr.tso_segsz);
1606 	XNB_ASSERT(pkt.extra.type == XEN_NETIF_EXTRA_TYPE_GSO);
1607 	XNB_ASSERT(! (pkt.extra.flags & XEN_NETIF_EXTRA_FLAG_MORE));
1608 
1609 	safe_m_freem(&mbufc);
1610 }
1611 
1612 /** xnb_mbufc2pkt with insufficient space in the ring */
1613 static void
1614 xnb_mbufc2pkt_nospace(char *buffer, size_t buflen) {
1615 	struct xnb_pkt pkt;
1616 	size_t size = 14 * MCLBYTES / 3;
1617 	size_t size_remaining;
1618 	int free_slots = 2;
1619 	RING_IDX start = 3;
1620 	struct mbuf *mbufc, *m;
1621 	int error;
1622 
1623 	mbufc = m_getm(NULL, size, M_WAITOK, MT_DATA);
1624 	XNB_ASSERT(mbufc != NULL);
1625 	if (mbufc == NULL)
1626 		return;
1627 	mbufc->m_flags |= M_PKTHDR;
1628 
1629 	mbufc->m_pkthdr.len = size;
1630 	size_remaining = size;
1631 	for (m = mbufc; m != NULL; m = m->m_next) {
1632 		m->m_len = MAX(M_TRAILINGSPACE(m), size_remaining);
1633 		size_remaining -= m->m_len;
1634 	}
1635 
1636 	error = xnb_mbufc2pkt(mbufc, &pkt, start, free_slots);
1637 	XNB_ASSERT(error == EAGAIN);
1638 	XNB_ASSERT(! xnb_pkt_is_valid(&pkt));
1639 
1640 	safe_m_freem(&mbufc);
1641 }
1642 
1643 /**
1644  * xnb_rxpkt2gnttab on an empty packet.  Should return empty gnttab
1645  */
1646 static void
1647 xnb_rxpkt2gnttab_empty(char *buffer, size_t buflen)
1648 {
1649 	struct xnb_pkt pkt;
1650 	int nr_entries;
1651 	int free_slots = 60;
1652 	struct mbuf *mbuf;
1653 
1654 	mbuf = m_get(M_WAITOK, MT_DATA);
1655 
1656 	xnb_mbufc2pkt(mbuf, &pkt, 0, free_slots);
1657 	nr_entries = xnb_rxpkt2gnttab(&pkt, mbuf, xnb_unit_pvt.gnttab,
1658 			&xnb_unit_pvt.rxb, DOMID_FIRST_RESERVED);
1659 
1660 	XNB_ASSERT(nr_entries == 0);
1661 
1662 	safe_m_freem(&mbuf);
1663 }
1664 
1665 /** xnb_rxpkt2gnttab on a short packet without extra data */
1666 static void
1667 xnb_rxpkt2gnttab_short(char *buffer, size_t buflen) {
1668 	struct xnb_pkt pkt;
1669 	int nr_entries;
1670 	size_t size = 128;
1671 	int free_slots = 60;
1672 	RING_IDX start = 9;
1673 	struct netif_rx_request *req;
1674 	struct mbuf *mbuf;
1675 
1676 	mbuf = m_getm(NULL, size, M_WAITOK, MT_DATA);
1677 	mbuf->m_flags |= M_PKTHDR;
1678 	mbuf->m_pkthdr.len = size;
1679 	mbuf->m_len = size;
1680 
1681 	xnb_mbufc2pkt(mbuf, &pkt, start, free_slots);
1682 	req = RING_GET_REQUEST(&xnb_unit_pvt.rxf,
1683 			       xnb_unit_pvt.txf.req_prod_pvt);
1684 	req->gref = 7;
1685 
1686 	nr_entries = xnb_rxpkt2gnttab(&pkt, mbuf, xnb_unit_pvt.gnttab,
1687 				      &xnb_unit_pvt.rxb, DOMID_FIRST_RESERVED);
1688 
1689 	XNB_ASSERT(nr_entries == 1);
1690 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].len == size);
1691 	/* flags should indicate gref's for dest */
1692 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].flags & GNTCOPY_dest_gref);
1693 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].dest.offset == 0);
1694 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].source.domid == DOMID_SELF);
1695 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].source.offset == virt_to_offset(
1696 		   mtod(mbuf, vm_offset_t)));
1697 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].source.u.gmfn ==
1698 		   virt_to_mfn(mtod(mbuf, vm_offset_t)));
1699 	XNB_ASSERT(xnb_unit_pvt.gnttab[0].dest.domid == DOMID_FIRST_RESERVED);
1700 
1701 	safe_m_freem(&mbuf);
1702 }
1703 
1704 /**
1705  * xnb_rxpkt2gnttab on a packet with two different mbufs in a single chai
1706  */
1707 static void
1708 xnb_rxpkt2gnttab_2req(char *buffer, size_t buflen)
1709 {
1710 	struct xnb_pkt pkt;
1711 	int nr_entries;
1712 	int i, num_mbufs;
1713 	size_t total_granted_size = 0;
1714 	size_t size = MJUMPAGESIZE + 1;
1715 	int free_slots = 60;
1716 	RING_IDX start = 11;
1717 	struct netif_rx_request *req;
1718 	struct mbuf *mbuf, *m;
1719 
1720 	mbuf = m_getm(NULL, size, M_WAITOK, MT_DATA);
1721 	mbuf->m_flags |= M_PKTHDR;
1722 	mbuf->m_pkthdr.len = size;
1723 	mbuf->m_len = size;
1724 
1725 	xnb_mbufc2pkt(mbuf, &pkt, start, free_slots);
1726 
1727 	for (i = 0, m=mbuf; m != NULL; i++, m = m->m_next) {
1728 		req = RING_GET_REQUEST(&xnb_unit_pvt.rxf,
1729 		    xnb_unit_pvt.txf.req_prod_pvt);
1730 		req->gref = i;
1731 		req->id = 5;
1732 	}
1733 	num_mbufs = i;
1734 
1735 	nr_entries = xnb_rxpkt2gnttab(&pkt, mbuf, xnb_unit_pvt.gnttab,
1736 			&xnb_unit_pvt.rxb, DOMID_FIRST_RESERVED);
1737 
1738 	XNB_ASSERT(nr_entries >= num_mbufs);
1739 	for (i = 0; i < nr_entries; i++) {
1740 		int end_offset = xnb_unit_pvt.gnttab[i].len +
1741 			xnb_unit_pvt.gnttab[i].dest.offset;
1742 		XNB_ASSERT(end_offset <= PAGE_SIZE);
1743 		total_granted_size += xnb_unit_pvt.gnttab[i].len;
1744 	}
1745 	XNB_ASSERT(total_granted_size == size);
1746 }
1747 
1748 /**
1749  * xnb_rxpkt2rsp on an empty packet.  Shouldn't make any response
1750  */
1751 static void
1752 xnb_rxpkt2rsp_empty(char *buffer, size_t buflen)
1753 {
1754 	struct xnb_pkt pkt;
1755 	int nr_entries;
1756 	int nr_reqs;
1757 	int free_slots = 60;
1758 	netif_rx_back_ring_t rxb_backup = xnb_unit_pvt.rxb;
1759 	netif_rx_sring_t rxs_backup = *xnb_unit_pvt.rxs;
1760 	struct mbuf *mbuf;
1761 
1762 	mbuf = m_get(M_WAITOK, MT_DATA);
1763 
1764 	xnb_mbufc2pkt(mbuf, &pkt, 0, free_slots);
1765 	nr_entries = xnb_rxpkt2gnttab(&pkt, mbuf, xnb_unit_pvt.gnttab,
1766 			&xnb_unit_pvt.rxb, DOMID_FIRST_RESERVED);
1767 
1768 	nr_reqs = xnb_rxpkt2rsp(&pkt, xnb_unit_pvt.gnttab, nr_entries,
1769 	    &xnb_unit_pvt.rxb);
1770 	XNB_ASSERT(nr_reqs == 0);
1771 	XNB_ASSERT(
1772 	    memcmp(&rxb_backup, &xnb_unit_pvt.rxb, sizeof(rxb_backup)) == 0);
1773 	XNB_ASSERT(
1774 	    memcmp(&rxs_backup, xnb_unit_pvt.rxs, sizeof(rxs_backup)) == 0);
1775 
1776 	safe_m_freem(&mbuf);
1777 }
1778 
1779 /**
1780  * xnb_rxpkt2rsp on a short packet with no extras
1781  */
1782 static void
1783 xnb_rxpkt2rsp_short(char *buffer, size_t buflen)
1784 {
1785 	struct xnb_pkt pkt;
1786 	int nr_entries, nr_reqs;
1787 	size_t size = 128;
1788 	int free_slots = 60;
1789 	RING_IDX start = 5;
1790 	struct netif_rx_request *req;
1791 	struct netif_rx_response *rsp;
1792 	struct mbuf *mbuf;
1793 
1794 	mbuf = m_getm(NULL, size, M_WAITOK, MT_DATA);
1795 	mbuf->m_flags |= M_PKTHDR;
1796 	mbuf->m_pkthdr.len = size;
1797 	mbuf->m_len = size;
1798 
1799 	xnb_mbufc2pkt(mbuf, &pkt, start, free_slots);
1800 	req = RING_GET_REQUEST(&xnb_unit_pvt.rxf, start);
1801 	req->gref = 7;
1802 	xnb_unit_pvt.rxb.req_cons = start;
1803 	xnb_unit_pvt.rxb.rsp_prod_pvt = start;
1804 	xnb_unit_pvt.rxs->req_prod = start + 1;
1805 	xnb_unit_pvt.rxs->rsp_prod = start;
1806 
1807 	nr_entries = xnb_rxpkt2gnttab(&pkt, mbuf, xnb_unit_pvt.gnttab,
1808 			&xnb_unit_pvt.rxb, DOMID_FIRST_RESERVED);
1809 
1810 	nr_reqs = xnb_rxpkt2rsp(&pkt, xnb_unit_pvt.gnttab, nr_entries,
1811 	    &xnb_unit_pvt.rxb);
1812 
1813 	XNB_ASSERT(nr_reqs == 1);
1814 	XNB_ASSERT(xnb_unit_pvt.rxb.rsp_prod_pvt == start + 1);
1815 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.rxb, start);
1816 	XNB_ASSERT(rsp->id == req->id);
1817 	XNB_ASSERT(rsp->offset == 0);
1818 	XNB_ASSERT((rsp->flags & (NETRXF_more_data | NETRXF_extra_info)) == 0);
1819 	XNB_ASSERT(rsp->status == size);
1820 
1821 	safe_m_freem(&mbuf);
1822 }
1823 
1824 /**
1825  * xnb_rxpkt2rsp with extra data
1826  */
1827 static void
1828 xnb_rxpkt2rsp_extra(char *buffer, size_t buflen)
1829 {
1830 	struct xnb_pkt pkt;
1831 	int nr_entries, nr_reqs;
1832 	size_t size = 14;
1833 	int free_slots = 15;
1834 	RING_IDX start = 3;
1835 	uint16_t id = 49;
1836 	uint16_t gref = 65;
1837 	uint16_t mss = TCP_MSS - 40;
1838 	struct mbuf *mbufc;
1839 	struct netif_rx_request *req;
1840 	struct netif_rx_response *rsp;
1841 	struct netif_extra_info *ext;
1842 
1843 	mbufc = m_getm(NULL, size, M_WAITOK, MT_DATA);
1844 	XNB_ASSERT(mbufc != NULL);
1845 	if (mbufc == NULL)
1846 		return;
1847 
1848 	mbufc->m_flags |= M_PKTHDR;
1849 	mbufc->m_pkthdr.len = size;
1850 	mbufc->m_pkthdr.csum_flags |= CSUM_TSO;
1851 	mbufc->m_pkthdr.tso_segsz = mss;
1852 	mbufc->m_len = size;
1853 
1854 	xnb_mbufc2pkt(mbufc, &pkt, start, free_slots);
1855 	req = RING_GET_REQUEST(&xnb_unit_pvt.rxf, start);
1856 	req->id = id;
1857 	req->gref = gref;
1858 	req = RING_GET_REQUEST(&xnb_unit_pvt.rxf, start + 1);
1859 	req->id = id + 1;
1860 	req->gref = gref + 1;
1861 	xnb_unit_pvt.rxb.req_cons = start;
1862 	xnb_unit_pvt.rxb.rsp_prod_pvt = start;
1863 	xnb_unit_pvt.rxs->req_prod = start + 2;
1864 	xnb_unit_pvt.rxs->rsp_prod = start;
1865 
1866 	nr_entries = xnb_rxpkt2gnttab(&pkt, mbufc, xnb_unit_pvt.gnttab,
1867 			&xnb_unit_pvt.rxb, DOMID_FIRST_RESERVED);
1868 
1869 	nr_reqs = xnb_rxpkt2rsp(&pkt, xnb_unit_pvt.gnttab, nr_entries,
1870 	    &xnb_unit_pvt.rxb);
1871 
1872 	XNB_ASSERT(nr_reqs == 2);
1873 	XNB_ASSERT(xnb_unit_pvt.rxb.rsp_prod_pvt == start + 2);
1874 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.rxb, start);
1875 	XNB_ASSERT(rsp->id == id);
1876 	XNB_ASSERT((rsp->flags & NETRXF_more_data) == 0);
1877 	XNB_ASSERT((rsp->flags & NETRXF_extra_info));
1878 	XNB_ASSERT((rsp->flags & NETRXF_data_validated));
1879 	XNB_ASSERT((rsp->flags & NETRXF_csum_blank));
1880 	XNB_ASSERT(rsp->status == size);
1881 
1882 	ext = (struct netif_extra_info*)
1883 		RING_GET_RESPONSE(&xnb_unit_pvt.rxb, start + 1);
1884 	XNB_ASSERT(ext->type == XEN_NETIF_EXTRA_TYPE_GSO);
1885 	XNB_ASSERT(! (ext->flags & XEN_NETIF_EXTRA_FLAG_MORE));
1886 	XNB_ASSERT(ext->u.gso.size == mss);
1887 	XNB_ASSERT(ext->u.gso.type == XEN_NETIF_EXTRA_TYPE_GSO);
1888 
1889 	safe_m_freem(&mbufc);
1890 }
1891 
1892 /**
1893  * xnb_rxpkt2rsp on a packet with more than a pages's worth of data.  It should
1894  * generate two response slot
1895  */
1896 static void
1897 xnb_rxpkt2rsp_2slots(char *buffer, size_t buflen)
1898 {
1899 	struct xnb_pkt pkt;
1900 	int nr_entries, nr_reqs;
1901 	size_t size = PAGE_SIZE + 100;
1902 	int free_slots = 3;
1903 	uint16_t id1 = 17;
1904 	uint16_t id2 = 37;
1905 	uint16_t gref1 = 24;
1906 	uint16_t gref2 = 34;
1907 	RING_IDX start = 15;
1908 	struct netif_rx_request *req;
1909 	struct netif_rx_response *rsp;
1910 	struct mbuf *mbuf;
1911 
1912 	mbuf = m_getm(NULL, size, M_WAITOK, MT_DATA);
1913 	mbuf->m_flags |= M_PKTHDR;
1914 	mbuf->m_pkthdr.len = size;
1915 	if (mbuf->m_next != NULL) {
1916 		size_t first_len = MIN(M_TRAILINGSPACE(mbuf), size);
1917 		mbuf->m_len = first_len;
1918 		mbuf->m_next->m_len = size - first_len;
1919 
1920 	} else {
1921 		mbuf->m_len = size;
1922 	}
1923 
1924 	xnb_mbufc2pkt(mbuf, &pkt, start, free_slots);
1925 	req = RING_GET_REQUEST(&xnb_unit_pvt.rxf, start);
1926 	req->gref = gref1;
1927 	req->id = id1;
1928 	req = RING_GET_REQUEST(&xnb_unit_pvt.rxf, start + 1);
1929 	req->gref = gref2;
1930 	req->id = id2;
1931 	xnb_unit_pvt.rxb.req_cons = start;
1932 	xnb_unit_pvt.rxb.rsp_prod_pvt = start;
1933 	xnb_unit_pvt.rxs->req_prod = start + 2;
1934 	xnb_unit_pvt.rxs->rsp_prod = start;
1935 
1936 	nr_entries = xnb_rxpkt2gnttab(&pkt, mbuf, xnb_unit_pvt.gnttab,
1937 			&xnb_unit_pvt.rxb, DOMID_FIRST_RESERVED);
1938 
1939 	nr_reqs = xnb_rxpkt2rsp(&pkt, xnb_unit_pvt.gnttab, nr_entries,
1940 	    &xnb_unit_pvt.rxb);
1941 
1942 	XNB_ASSERT(nr_reqs == 2);
1943 	XNB_ASSERT(xnb_unit_pvt.rxb.rsp_prod_pvt == start + 2);
1944 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.rxb, start);
1945 	XNB_ASSERT(rsp->id == id1);
1946 	XNB_ASSERT(rsp->offset == 0);
1947 	XNB_ASSERT((rsp->flags & NETRXF_extra_info) == 0);
1948 	XNB_ASSERT(rsp->flags & NETRXF_more_data);
1949 	XNB_ASSERT(rsp->status == PAGE_SIZE);
1950 
1951 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.rxb, start + 1);
1952 	XNB_ASSERT(rsp->id == id2);
1953 	XNB_ASSERT(rsp->offset == 0);
1954 	XNB_ASSERT((rsp->flags & NETRXF_extra_info) == 0);
1955 	XNB_ASSERT(! (rsp->flags & NETRXF_more_data));
1956 	XNB_ASSERT(rsp->status == size - PAGE_SIZE);
1957 
1958 	safe_m_freem(&mbuf);
1959 }
1960 
1961 /** xnb_rxpkt2rsp on a grant table with two sub-page entries */
1962 static void
1963 xnb_rxpkt2rsp_2short(char *buffer, size_t buflen) {
1964 	struct xnb_pkt pkt;
1965 	int nr_reqs, nr_entries;
1966 	size_t size1 = MHLEN - 5;
1967 	size_t size2 = MHLEN - 15;
1968 	int free_slots = 32;
1969 	RING_IDX start = 14;
1970 	uint16_t id = 47;
1971 	uint16_t gref = 54;
1972 	struct netif_rx_request *req;
1973 	struct netif_rx_response *rsp;
1974 	struct mbuf *mbufc;
1975 
1976 	mbufc = m_getm(NULL, size1, M_WAITOK, MT_DATA);
1977 	XNB_ASSERT(mbufc != NULL);
1978 	if (mbufc == NULL)
1979 		return;
1980 	mbufc->m_flags |= M_PKTHDR;
1981 
1982 	m_getm(mbufc, size2, M_WAITOK, MT_DATA);
1983 	XNB_ASSERT(mbufc->m_next != NULL);
1984 	mbufc->m_pkthdr.len = size1 + size2;
1985 	mbufc->m_len = size1;
1986 	mbufc->m_next->m_len = size2;
1987 
1988 	xnb_mbufc2pkt(mbufc, &pkt, start, free_slots);
1989 
1990 	req = RING_GET_REQUEST(&xnb_unit_pvt.rxf, start);
1991 	req->gref = gref;
1992 	req->id = id;
1993 	xnb_unit_pvt.rxb.req_cons = start;
1994 	xnb_unit_pvt.rxb.rsp_prod_pvt = start;
1995 	xnb_unit_pvt.rxs->req_prod = start + 1;
1996 	xnb_unit_pvt.rxs->rsp_prod = start;
1997 
1998 	nr_entries = xnb_rxpkt2gnttab(&pkt, mbufc, xnb_unit_pvt.gnttab,
1999 			&xnb_unit_pvt.rxb, DOMID_FIRST_RESERVED);
2000 
2001 	nr_reqs = xnb_rxpkt2rsp(&pkt, xnb_unit_pvt.gnttab, nr_entries,
2002 	    &xnb_unit_pvt.rxb);
2003 
2004 	XNB_ASSERT(nr_entries == 2);
2005 	XNB_ASSERT(nr_reqs == 1);
2006 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.rxb, start);
2007 	XNB_ASSERT(rsp->id == id);
2008 	XNB_ASSERT(rsp->status == size1 + size2);
2009 	XNB_ASSERT(rsp->offset == 0);
2010 	XNB_ASSERT(! (rsp->flags & (NETRXF_more_data | NETRXF_extra_info)));
2011 
2012 	safe_m_freem(&mbufc);
2013 }
2014 
2015 /**
2016  * xnb_rxpkt2rsp on a long packet with a hypervisor gnttab_copy error
2017  * Note: this test will result in an error message being printed to the console
2018  * such as:
2019  * xnb(xnb_rxpkt2rsp:1720): Got error -1 for hypervisor gnttab_copy status
2020  */
2021 static void
2022 xnb_rxpkt2rsp_copyerror(char *buffer, size_t buflen)
2023 {
2024 	struct xnb_pkt pkt;
2025 	int nr_entries, nr_reqs;
2026 	int id = 7;
2027 	int gref = 42;
2028 	uint16_t canary = 6859;
2029 	size_t size = 7 * MCLBYTES;
2030 	int free_slots = 9;
2031 	RING_IDX start = 2;
2032 	struct netif_rx_request *req;
2033 	struct netif_rx_response *rsp;
2034 	struct mbuf *mbuf;
2035 
2036 	mbuf = m_getm(NULL, size, M_WAITOK, MT_DATA);
2037 	mbuf->m_flags |= M_PKTHDR;
2038 	mbuf->m_pkthdr.len = size;
2039 	mbuf->m_len = size;
2040 
2041 	xnb_mbufc2pkt(mbuf, &pkt, start, free_slots);
2042 	req = RING_GET_REQUEST(&xnb_unit_pvt.rxf, start);
2043 	req->gref = gref;
2044 	req->id = id;
2045 	xnb_unit_pvt.rxb.req_cons = start;
2046 	xnb_unit_pvt.rxb.rsp_prod_pvt = start;
2047 	xnb_unit_pvt.rxs->req_prod = start + 1;
2048 	xnb_unit_pvt.rxs->rsp_prod = start;
2049 	req = RING_GET_REQUEST(&xnb_unit_pvt.rxf, start + 1);
2050 	req->gref = canary;
2051 	req->id = canary;
2052 
2053 	nr_entries = xnb_rxpkt2gnttab(&pkt, mbuf, xnb_unit_pvt.gnttab,
2054 			&xnb_unit_pvt.rxb, DOMID_FIRST_RESERVED);
2055 	/* Inject the error*/
2056 	xnb_unit_pvt.gnttab[2].status = GNTST_general_error;
2057 
2058 	nr_reqs = xnb_rxpkt2rsp(&pkt, xnb_unit_pvt.gnttab, nr_entries,
2059 	    &xnb_unit_pvt.rxb);
2060 
2061 	XNB_ASSERT(nr_reqs == 1);
2062 	XNB_ASSERT(xnb_unit_pvt.rxb.rsp_prod_pvt == start + 1);
2063 	rsp = RING_GET_RESPONSE(&xnb_unit_pvt.rxb, start);
2064 	XNB_ASSERT(rsp->id == id);
2065 	XNB_ASSERT(rsp->status == NETIF_RSP_ERROR);
2066 	req = RING_GET_REQUEST(&xnb_unit_pvt.rxf, start + 1);
2067 	XNB_ASSERT(req->gref == canary);
2068 	XNB_ASSERT(req->id == canary);
2069 
2070 	safe_m_freem(&mbuf);
2071 }
2072 
2073 #if defined(INET) || defined(INET6)
2074 /**
2075  * xnb_add_mbuf_cksum on an ARP request packet
2076  */
2077 static void
2078 xnb_add_mbuf_cksum_arp(char *buffer, size_t buflen)
2079 {
2080 	const size_t pkt_len = sizeof(struct ether_header) +
2081 		sizeof(struct ether_arp);
2082 	struct mbuf *mbufc;
2083 	struct ether_header *eh;
2084 	struct ether_arp *ep;
2085 	unsigned char pkt_orig[pkt_len];
2086 
2087 	mbufc = m_getm(NULL, pkt_len, M_WAITOK, MT_DATA);
2088 	/* Fill in an example arp request */
2089 	eh = mtod(mbufc, struct ether_header*);
2090 	eh->ether_dhost[0] = 0xff;
2091 	eh->ether_dhost[1] = 0xff;
2092 	eh->ether_dhost[2] = 0xff;
2093 	eh->ether_dhost[3] = 0xff;
2094 	eh->ether_dhost[4] = 0xff;
2095 	eh->ether_dhost[5] = 0xff;
2096 	eh->ether_shost[0] = 0x00;
2097 	eh->ether_shost[1] = 0x15;
2098 	eh->ether_shost[2] = 0x17;
2099 	eh->ether_shost[3] = 0xe9;
2100 	eh->ether_shost[4] = 0x30;
2101 	eh->ether_shost[5] = 0x68;
2102 	eh->ether_type = htons(ETHERTYPE_ARP);
2103 	ep = (struct ether_arp*)(eh + 1);
2104 	ep->ea_hdr.ar_hrd = htons(ARPHRD_ETHER);
2105 	ep->ea_hdr.ar_pro = htons(ETHERTYPE_IP);
2106 	ep->ea_hdr.ar_hln = 6;
2107 	ep->ea_hdr.ar_pln = 4;
2108 	ep->ea_hdr.ar_op = htons(ARPOP_REQUEST);
2109 	ep->arp_sha[0] = 0x00;
2110 	ep->arp_sha[1] = 0x15;
2111 	ep->arp_sha[2] = 0x17;
2112 	ep->arp_sha[3] = 0xe9;
2113 	ep->arp_sha[4] = 0x30;
2114 	ep->arp_sha[5] = 0x68;
2115 	ep->arp_spa[0] = 0xc0;
2116 	ep->arp_spa[1] = 0xa8;
2117 	ep->arp_spa[2] = 0x0a;
2118 	ep->arp_spa[3] = 0x04;
2119 	bzero(&(ep->arp_tha), ETHER_ADDR_LEN);
2120 	ep->arp_tpa[0] = 0xc0;
2121 	ep->arp_tpa[1] = 0xa8;
2122 	ep->arp_tpa[2] = 0x0a;
2123 	ep->arp_tpa[3] = 0x06;
2124 
2125 	/* fill in the length field */
2126 	mbufc->m_len = pkt_len;
2127 	mbufc->m_pkthdr.len = pkt_len;
2128 	/* indicate that the netfront uses hw-assisted checksums */
2129 	mbufc->m_pkthdr.csum_flags = CSUM_IP_CHECKED | CSUM_IP_VALID   |
2130 				CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2131 
2132 	/* Make a backup copy of the packet */
2133 	bcopy(mtod(mbufc, const void*), pkt_orig, pkt_len);
2134 
2135 	/* Function under test */
2136 	xnb_add_mbuf_cksum(mbufc);
2137 
2138 	/* Verify that the packet's data did not change */
2139 	XNB_ASSERT(bcmp(mtod(mbufc, const void*), pkt_orig, pkt_len) == 0);
2140 	m_freem(mbufc);
2141 }
2142 
2143 /**
2144  * Helper function that populates the ethernet header and IP header used by
2145  * some of the xnb_add_mbuf_cksum unit tests.  m must already be allocated
2146  * and must be large enough
2147  */
2148 static void
2149 xnb_fill_eh_and_ip(struct mbuf *m, uint16_t ip_len, uint16_t ip_id,
2150 		   uint16_t ip_p, uint16_t ip_off, uint16_t ip_sum)
2151 {
2152 	struct ether_header *eh;
2153 	struct ip *iph;
2154 
2155 	eh = mtod(m, struct ether_header*);
2156 	eh->ether_dhost[0] = 0x00;
2157 	eh->ether_dhost[1] = 0x16;
2158 	eh->ether_dhost[2] = 0x3e;
2159 	eh->ether_dhost[3] = 0x23;
2160 	eh->ether_dhost[4] = 0x50;
2161 	eh->ether_dhost[5] = 0x0b;
2162 	eh->ether_shost[0] = 0x00;
2163 	eh->ether_shost[1] = 0x16;
2164 	eh->ether_shost[2] = 0x30;
2165 	eh->ether_shost[3] = 0x00;
2166 	eh->ether_shost[4] = 0x00;
2167 	eh->ether_shost[5] = 0x00;
2168 	eh->ether_type = htons(ETHERTYPE_IP);
2169 	iph = (struct ip*)(eh + 1);
2170 	iph->ip_hl = 0x5;	/* 5 dwords == 20 bytes */
2171 	iph->ip_v = 4;		/* IP v4 */
2172 	iph->ip_tos = 0;
2173 	iph->ip_len = htons(ip_len);
2174 	iph->ip_id = htons(ip_id);
2175 	iph->ip_off = htons(ip_off);
2176 	iph->ip_ttl = 64;
2177 	iph->ip_p = ip_p;
2178 	iph->ip_sum = htons(ip_sum);
2179 	iph->ip_src.s_addr = htonl(0xc0a80a04);
2180 	iph->ip_dst.s_addr = htonl(0xc0a80a05);
2181 }
2182 
2183 /**
2184  * xnb_add_mbuf_cksum on an ICMP packet, based on a tcpdump of an actual
2185  * ICMP packet
2186  */
2187 static void
2188 xnb_add_mbuf_cksum_icmp(char *buffer, size_t buflen)
2189 {
2190 	const size_t icmp_len = 64;	/* set by ping(1) */
2191 	const size_t pkt_len = sizeof(struct ether_header) +
2192 		sizeof(struct ip) + icmp_len;
2193 	struct mbuf *mbufc;
2194 	struct ether_header *eh;
2195 	struct ip *iph;
2196 	struct icmp *icmph;
2197 	unsigned char pkt_orig[icmp_len];
2198 	uint32_t *tv_field;
2199 	uint8_t *data_payload;
2200 	int i;
2201 	const uint16_t ICMP_CSUM = 0xaed7;
2202 	const uint16_t IP_CSUM = 0xe533;
2203 
2204 	mbufc = m_getm(NULL, pkt_len, M_WAITOK, MT_DATA);
2205 	/* Fill in an example ICMP ping request */
2206 	eh = mtod(mbufc, struct ether_header*);
2207 	xnb_fill_eh_and_ip(mbufc, 84, 28, IPPROTO_ICMP, 0, 0);
2208 	iph = (struct ip*)(eh + 1);
2209 	icmph = (struct icmp*)(iph + 1);
2210 	icmph->icmp_type = ICMP_ECHO;
2211 	icmph->icmp_code = 0;
2212 	icmph->icmp_cksum = htons(ICMP_CSUM);
2213 	icmph->icmp_id = htons(31492);
2214 	icmph->icmp_seq = htons(0);
2215 	/*
2216 	 * ping(1) uses bcopy to insert a native-endian timeval after icmp_seq.
2217 	 * For this test, we will set the bytes individually for portability.
2218 	 */
2219 	tv_field = (uint32_t*)(&(icmph->icmp_hun));
2220 	tv_field[0] = 0x4f02cfac;
2221 	tv_field[1] = 0x0007c46a;
2222 	/*
2223 	 * Remainder of packet is an incrmenting 8 bit integer, starting with 8
2224 	 */
2225 	data_payload = (uint8_t*)(&tv_field[2]);
2226 	for (i = 8; i < 37; i++) {
2227 		*data_payload++ = i;
2228 	}
2229 
2230 	/* fill in the length field */
2231 	mbufc->m_len = pkt_len;
2232 	mbufc->m_pkthdr.len = pkt_len;
2233 	/* indicate that the netfront uses hw-assisted checksums */
2234 	mbufc->m_pkthdr.csum_flags = CSUM_IP_CHECKED | CSUM_IP_VALID   |
2235 				CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2236 
2237 	bcopy(mtod(mbufc, const void*), pkt_orig, icmp_len);
2238 	/* Function under test */
2239 	xnb_add_mbuf_cksum(mbufc);
2240 
2241 	/* Check the IP checksum */
2242 	XNB_ASSERT(iph->ip_sum == htons(IP_CSUM));
2243 
2244 	/* Check that the ICMP packet did not change */
2245 	XNB_ASSERT(bcmp(icmph, pkt_orig, icmp_len));
2246 	m_freem(mbufc);
2247 }
2248 
2249 /**
2250  * xnb_add_mbuf_cksum on a UDP packet, based on a tcpdump of an actual
2251  * UDP packet
2252  */
2253 static void
2254 xnb_add_mbuf_cksum_udp(char *buffer, size_t buflen)
2255 {
2256 	const size_t udp_len = 16;
2257 	const size_t pkt_len = sizeof(struct ether_header) +
2258 		sizeof(struct ip) + udp_len;
2259 	struct mbuf *mbufc;
2260 	struct ether_header *eh;
2261 	struct ip *iph;
2262 	struct udphdr *udp;
2263 	uint8_t *data_payload;
2264 	const uint16_t IP_CSUM = 0xe56b;
2265 	const uint16_t UDP_CSUM = 0xdde2;
2266 
2267 	mbufc = m_getm(NULL, pkt_len, M_WAITOK, MT_DATA);
2268 	/* Fill in an example UDP packet made by 'uname | nc -u <host> 2222 */
2269 	eh = mtod(mbufc, struct ether_header*);
2270 	xnb_fill_eh_and_ip(mbufc, 36, 4, IPPROTO_UDP, 0, 0xbaad);
2271 	iph = (struct ip*)(eh + 1);
2272 	udp = (struct udphdr*)(iph + 1);
2273 	udp->uh_sport = htons(0x51ae);
2274 	udp->uh_dport = htons(0x08ae);
2275 	udp->uh_ulen = htons(udp_len);
2276 	udp->uh_sum = htons(0xbaad);  /* xnb_add_mbuf_cksum will fill this in */
2277 	data_payload = (uint8_t*)(udp + 1);
2278 	data_payload[0] = 'F';
2279 	data_payload[1] = 'r';
2280 	data_payload[2] = 'e';
2281 	data_payload[3] = 'e';
2282 	data_payload[4] = 'B';
2283 	data_payload[5] = 'S';
2284 	data_payload[6] = 'D';
2285 	data_payload[7] = '\n';
2286 
2287 	/* fill in the length field */
2288 	mbufc->m_len = pkt_len;
2289 	mbufc->m_pkthdr.len = pkt_len;
2290 	/* indicate that the netfront uses hw-assisted checksums */
2291 	mbufc->m_pkthdr.csum_flags = CSUM_IP_CHECKED | CSUM_IP_VALID   |
2292 				CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2293 
2294 	/* Function under test */
2295 	xnb_add_mbuf_cksum(mbufc);
2296 
2297 	/* Check the checksums */
2298 	XNB_ASSERT(iph->ip_sum == htons(IP_CSUM));
2299 	XNB_ASSERT(udp->uh_sum == htons(UDP_CSUM));
2300 
2301 	m_freem(mbufc);
2302 }
2303 
2304 /**
2305  * Helper function that populates a TCP packet used by all of the
2306  * xnb_add_mbuf_cksum tcp unit tests.  m must already be allocated and must be
2307  * large enough
2308  */
2309 static void
2310 xnb_fill_tcp(struct mbuf *m)
2311 {
2312 	struct ether_header *eh;
2313 	struct ip *iph;
2314 	struct tcphdr *tcp;
2315 	uint32_t *options;
2316 	uint8_t *data_payload;
2317 
2318 	/* Fill in an example TCP packet made by 'uname | nc <host> 2222' */
2319 	eh = mtod(m, struct ether_header*);
2320 	xnb_fill_eh_and_ip(m, 60, 8, IPPROTO_TCP, IP_DF, 0);
2321 	iph = (struct ip*)(eh + 1);
2322 	tcp = (struct tcphdr*)(iph + 1);
2323 	tcp->th_sport = htons(0x9cd9);
2324 	tcp->th_dport = htons(2222);
2325 	tcp->th_seq = htonl(0x00f72b10);
2326 	tcp->th_ack = htonl(0x7f37ba6c);
2327 	tcp->th_x2 = 0;
2328 	tcp->th_off = 8;
2329 	tcp->th_flags = 0x18;
2330 	tcp->th_win = htons(0x410);
2331 	/* th_sum is incorrect; will be inserted by function under test */
2332 	tcp->th_sum = htons(0xbaad);
2333 	tcp->th_urp = htons(0);
2334 	/*
2335 	 * The following 12 bytes of options encode:
2336 	 * [nop, nop, TS val 33247 ecr 3457687679]
2337 	 */
2338 	options = (uint32_t*)(tcp + 1);
2339 	options[0] = htonl(0x0101080a);
2340 	options[1] = htonl(0x000081df);
2341 	options[2] = htonl(0xce18207f);
2342 	data_payload = (uint8_t*)(&options[3]);
2343 	data_payload[0] = 'F';
2344 	data_payload[1] = 'r';
2345 	data_payload[2] = 'e';
2346 	data_payload[3] = 'e';
2347 	data_payload[4] = 'B';
2348 	data_payload[5] = 'S';
2349 	data_payload[6] = 'D';
2350 	data_payload[7] = '\n';
2351 }
2352 
2353 /**
2354  * xnb_add_mbuf_cksum on a TCP packet, based on a tcpdump of an actual TCP
2355  * packet
2356  */
2357 static void
2358 xnb_add_mbuf_cksum_tcp(char *buffer, size_t buflen)
2359 {
2360 	const size_t payload_len = 8;
2361 	const size_t tcp_options_len = 12;
2362 	const size_t pkt_len = sizeof(struct ether_header) + sizeof(struct ip) +
2363 	    sizeof(struct tcphdr) + tcp_options_len + payload_len;
2364 	struct mbuf *mbufc;
2365 	struct ether_header *eh;
2366 	struct ip *iph;
2367 	struct tcphdr *tcp;
2368 	const uint16_t IP_CSUM = 0xa55a;
2369 	const uint16_t TCP_CSUM = 0x2f64;
2370 
2371 	mbufc = m_getm(NULL, pkt_len, M_WAITOK, MT_DATA);
2372 	/* Fill in an example TCP packet made by 'uname | nc <host> 2222' */
2373 	xnb_fill_tcp(mbufc);
2374 	eh = mtod(mbufc, struct ether_header*);
2375 	iph = (struct ip*)(eh + 1);
2376 	tcp = (struct tcphdr*)(iph + 1);
2377 
2378 	/* fill in the length field */
2379 	mbufc->m_len = pkt_len;
2380 	mbufc->m_pkthdr.len = pkt_len;
2381 	/* indicate that the netfront uses hw-assisted checksums */
2382 	mbufc->m_pkthdr.csum_flags = CSUM_IP_CHECKED | CSUM_IP_VALID   |
2383 				CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2384 
2385 	/* Function under test */
2386 	xnb_add_mbuf_cksum(mbufc);
2387 
2388 	/* Check the checksums */
2389 	XNB_ASSERT(iph->ip_sum == htons(IP_CSUM));
2390 	XNB_ASSERT(tcp->th_sum == htons(TCP_CSUM));
2391 
2392 	m_freem(mbufc);
2393 }
2394 
2395 /**
2396  * xnb_add_mbuf_cksum on a TCP packet that does not use HW assisted checksums
2397  */
2398 static void
2399 xnb_add_mbuf_cksum_tcp_swcksum(char *buffer, size_t buflen)
2400 {
2401 	const size_t payload_len = 8;
2402 	const size_t tcp_options_len = 12;
2403 	const size_t pkt_len = sizeof(struct ether_header) + sizeof(struct ip) +
2404 	    sizeof(struct tcphdr) + tcp_options_len + payload_len;
2405 	struct mbuf *mbufc;
2406 	struct ether_header *eh;
2407 	struct ip *iph;
2408 	struct tcphdr *tcp;
2409 	/* Use deliberately bad checksums, and verify that they don't get */
2410 	/* corrected by xnb_add_mbuf_cksum */
2411 	const uint16_t IP_CSUM = 0xdead;
2412 	const uint16_t TCP_CSUM = 0xbeef;
2413 
2414 	mbufc = m_getm(NULL, pkt_len, M_WAITOK, MT_DATA);
2415 	/* Fill in an example TCP packet made by 'uname | nc <host> 2222' */
2416 	xnb_fill_tcp(mbufc);
2417 	eh = mtod(mbufc, struct ether_header*);
2418 	iph = (struct ip*)(eh + 1);
2419 	iph->ip_sum = htons(IP_CSUM);
2420 	tcp = (struct tcphdr*)(iph + 1);
2421 	tcp->th_sum = htons(TCP_CSUM);
2422 
2423 	/* fill in the length field */
2424 	mbufc->m_len = pkt_len;
2425 	mbufc->m_pkthdr.len = pkt_len;
2426 	/* indicate that the netfront does not use hw-assisted checksums */
2427 	mbufc->m_pkthdr.csum_flags = 0;
2428 
2429 	/* Function under test */
2430 	xnb_add_mbuf_cksum(mbufc);
2431 
2432 	/* Check that the checksums didn't change */
2433 	XNB_ASSERT(iph->ip_sum == htons(IP_CSUM));
2434 	XNB_ASSERT(tcp->th_sum == htons(TCP_CSUM));
2435 
2436 	m_freem(mbufc);
2437 }
2438 #endif /* INET || INET6 */
2439 
2440 /**
2441  * sscanf on unsigned chars
2442  */
2443 static void
2444 xnb_sscanf_hhu(char *buffer, size_t buflen)
2445 {
2446 	const char mystr[] = "137";
2447 	uint8_t dest[12];
2448 	int i;
2449 
2450 	for (i = 0; i < 12; i++)
2451 		dest[i] = 'X';
2452 
2453 	XNB_ASSERT(sscanf(mystr, "%hhu", &dest[4]) == 1);
2454 	for (i = 0; i < 12; i++)
2455 		XNB_ASSERT(dest[i] == (i == 4 ? 137 : 'X'));
2456 }
2457 
2458 /**
2459  * sscanf on signed chars
2460  */
2461 static void
2462 xnb_sscanf_hhd(char *buffer, size_t buflen)
2463 {
2464 	const char mystr[] = "-27";
2465 	int8_t dest[12];
2466 	int i;
2467 
2468 	for (i = 0; i < 12; i++)
2469 		dest[i] = 'X';
2470 
2471 	XNB_ASSERT(sscanf(mystr, "%hhd", &dest[4]) == 1);
2472 	for (i = 0; i < 12; i++)
2473 		XNB_ASSERT(dest[i] == (i == 4 ? -27 : 'X'));
2474 }
2475 
2476 /**
2477  * sscanf on signed long longs
2478  */
2479 static void
2480 xnb_sscanf_lld(char *buffer, size_t buflen)
2481 {
2482 	const char mystr[] = "-123456789012345";	/* about -2**47 */
2483 	long long dest[3];
2484 	int i;
2485 
2486 	for (i = 0; i < 3; i++)
2487 		dest[i] = (long long)0xdeadbeefdeadbeef;
2488 
2489 	XNB_ASSERT(sscanf(mystr, "%lld", &dest[1]) == 1);
2490 	for (i = 0; i < 3; i++)
2491 		XNB_ASSERT(dest[i] == (i != 1 ? (long long)0xdeadbeefdeadbeef :
2492 		    -123456789012345));
2493 }
2494 
2495 /**
2496  * sscanf on unsigned long longs
2497  */
2498 static void
2499 xnb_sscanf_llu(char *buffer, size_t buflen)
2500 {
2501 	const char mystr[] = "12802747070103273189";
2502 	unsigned long long dest[3];
2503 	int i;
2504 
2505 	for (i = 0; i < 3; i++)
2506 		dest[i] = (long long)0xdeadbeefdeadbeef;
2507 
2508 	XNB_ASSERT(sscanf(mystr, "%llu", &dest[1]) == 1);
2509 	for (i = 0; i < 3; i++)
2510 		XNB_ASSERT(dest[i] == (i != 1 ? (long long)0xdeadbeefdeadbeef :
2511 		    12802747070103273189ull));
2512 }
2513 
2514 /**
2515  * sscanf on unsigned short short n's
2516  */
2517 static void
2518 xnb_sscanf_hhn(char *buffer, size_t buflen)
2519 {
2520 	const char mystr[] =
2521 	    "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f"
2522 	    "202122232425262728292a2b2c2d2e2f303132333435363738393a3b3c3d3e3f"
2523 	    "404142434445464748494a4b4c4d4e4f505152535455565758595a5b5c5d5e5f";
2524 	unsigned char dest[12];
2525 	int i;
2526 
2527 	for (i = 0; i < 12; i++)
2528 		dest[i] = (unsigned char)'X';
2529 
2530 	XNB_ASSERT(sscanf(mystr,
2531 	    "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f"
2532 	    "202122232425262728292a2b2c2d2e2f303132333435363738393a3b3c3d3e3f"
2533 	    "404142434445464748494a4b4c4d4e4f%hhn", &dest[4]) == 0);
2534 	for (i = 0; i < 12; i++)
2535 		XNB_ASSERT(dest[i] == (i == 4 ? 160 : 'X'));
2536 }
2537