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1// SPDX-License-Identifier: GPL-2.02/* Simple test of virtio code, entirely in userpsace. */3#define _GNU_SOURCE4#include <sched.h>5#include <err.h>6#include <linux/kernel.h>7#include <linux/err.h>8#include <linux/virtio.h>9#include <linux/vringh.h>10#include <linux/virtio_ring.h>11#include <linux/virtio_config.h>12#include <linux/uaccess.h>13#include <sys/types.h>14#include <sys/stat.h>15#include <sys/mman.h>16#include <sys/wait.h>17#include <fcntl.h>18 19#define USER_MEM (1024*1024)20void *__user_addr_min, *__user_addr_max;21void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end;22static u64 user_addr_offset;23 24#define RINGSIZE 25625#define ALIGN 409626 27static bool never_notify_host(struct virtqueue *vq)28{29	abort();30}31 32static void never_callback_guest(struct virtqueue *vq)33{34	abort();35}36 37static bool getrange_iov(struct vringh *vrh, u64 addr, struct vringh_range *r)38{39	if (addr < (u64)(unsigned long)__user_addr_min - user_addr_offset)40		return false;41	if (addr >= (u64)(unsigned long)__user_addr_max - user_addr_offset)42		return false;43 44	r->start = (u64)(unsigned long)__user_addr_min - user_addr_offset;45	r->end_incl = (u64)(unsigned long)__user_addr_max - 1 - user_addr_offset;46	r->offset = user_addr_offset;47	return true;48}49 50/* We return single byte ranges. */51static bool getrange_slow(struct vringh *vrh, u64 addr, struct vringh_range *r)52{53	if (addr < (u64)(unsigned long)__user_addr_min - user_addr_offset)54		return false;55	if (addr >= (u64)(unsigned long)__user_addr_max - user_addr_offset)56		return false;57 58	r->start = addr;59	r->end_incl = r->start;60	r->offset = user_addr_offset;61	return true;62}63 64struct guest_virtio_device {65	struct virtio_device vdev;66	int to_host_fd;67	unsigned long notifies;68};69 70static bool parallel_notify_host(struct virtqueue *vq)71{72	int rc;73	struct guest_virtio_device *gvdev;74 75	gvdev = container_of(vq->vdev, struct guest_virtio_device, vdev);76	rc = write(gvdev->to_host_fd, "", 1);77	if (rc < 0)78		return false;79	gvdev->notifies++;80	return true;81}82 83static bool no_notify_host(struct virtqueue *vq)84{85	return true;86}87 88#define NUM_XFERS (10000000)89 90/* We aim for two "distant" cpus. */91static void find_cpus(unsigned int *first, unsigned int *last)92{93	unsigned int i;94 95	*first = -1U;96	*last = 0;97	for (i = 0; i < 4096; i++) {98		cpu_set_t set;99		CPU_ZERO(&set);100		CPU_SET(i, &set);101		if (sched_setaffinity(getpid(), sizeof(set), &set) == 0) {102			if (i < *first)103				*first = i;104			if (i > *last)105				*last = i;106		}107	}108}109 110/* Opencoded version for fast mode */111static inline int vringh_get_head(struct vringh *vrh, u16 *head)112{113	u16 avail_idx, i;114	int err;115 116	err = get_user(avail_idx, &vrh->vring.avail->idx);117	if (err)118		return err;119 120	if (vrh->last_avail_idx == avail_idx)121		return 0;122 123	/* Only get avail ring entries after they have been exposed by guest. */124	virtio_rmb(vrh->weak_barriers);125 126	i = vrh->last_avail_idx & (vrh->vring.num - 1);127 128	err = get_user(*head, &vrh->vring.avail->ring[i]);129	if (err)130		return err;131 132	vrh->last_avail_idx++;133	return 1;134}135 136static int parallel_test(u64 features,137			 bool (*getrange)(struct vringh *vrh,138					  u64 addr, struct vringh_range *r),139			 bool fast_vringh)140{141	void *host_map, *guest_map;142	int pipe_ret, fd, mapsize, to_guest[2], to_host[2];143	unsigned long xfers = 0, notifies = 0, receives = 0;144	unsigned int first_cpu, last_cpu;145	cpu_set_t cpu_set;146	char buf[128];147 148	/* Create real file to mmap. */149	fd = open("/tmp/vringh_test-file", O_RDWR|O_CREAT|O_TRUNC, 0600);150	if (fd < 0)151		err(1, "Opening /tmp/vringh_test-file");152 153	/* Extra room at the end for some data, and indirects */154	mapsize = vring_size(RINGSIZE, ALIGN)155		+ RINGSIZE * 2 * sizeof(int)156		+ RINGSIZE * 6 * sizeof(struct vring_desc);157	mapsize = (mapsize + getpagesize() - 1) & ~(getpagesize() - 1);158	ftruncate(fd, mapsize);159 160	/* Parent and child use separate addresses, to check our mapping logic! */161	host_map = mmap(NULL, mapsize, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);162	guest_map = mmap(NULL, mapsize, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);163 164	pipe_ret = pipe(to_guest);165	assert(!pipe_ret);166 167	pipe_ret = pipe(to_host);168	assert(!pipe_ret);169 170	CPU_ZERO(&cpu_set);171	find_cpus(&first_cpu, &last_cpu);172	printf("Using CPUS %u and %u\n", first_cpu, last_cpu);173	fflush(stdout);174 175	if (fork() != 0) {176		struct vringh vrh;177		int status, err, rlen = 0;178		char rbuf[5];179 180		/* We are the host: never access guest addresses! */181		munmap(guest_map, mapsize);182 183		__user_addr_min = host_map;184		__user_addr_max = __user_addr_min + mapsize;185		user_addr_offset = host_map - guest_map;186		assert(user_addr_offset);187 188		close(to_guest[0]);189		close(to_host[1]);190 191		vring_init(&vrh.vring, RINGSIZE, host_map, ALIGN);192		vringh_init_user(&vrh, features, RINGSIZE, true,193				 vrh.vring.desc, vrh.vring.avail, vrh.vring.used);194		CPU_SET(first_cpu, &cpu_set);195		if (sched_setaffinity(getpid(), sizeof(cpu_set), &cpu_set))196			errx(1, "Could not set affinity to cpu %u", first_cpu);197 198		while (xfers < NUM_XFERS) {199			struct iovec host_riov[2], host_wiov[2];200			struct vringh_iov riov, wiov;201			u16 head, written;202 203			if (fast_vringh) {204				for (;;) {205					err = vringh_get_head(&vrh, &head);206					if (err != 0)207						break;208					err = vringh_need_notify_user(&vrh);209					if (err < 0)210						errx(1, "vringh_need_notify_user: %i",211						     err);212					if (err) {213						write(to_guest[1], "", 1);214						notifies++;215					}216				}217				if (err != 1)218					errx(1, "vringh_get_head");219				written = 0;220				goto complete;221			} else {222				vringh_iov_init(&riov,223						host_riov,224						ARRAY_SIZE(host_riov));225				vringh_iov_init(&wiov,226						host_wiov,227						ARRAY_SIZE(host_wiov));228 229				err = vringh_getdesc_user(&vrh, &riov, &wiov,230							  getrange, &head);231			}232			if (err == 0) {233				err = vringh_need_notify_user(&vrh);234				if (err < 0)235					errx(1, "vringh_need_notify_user: %i",236					     err);237				if (err) {238					write(to_guest[1], "", 1);239					notifies++;240				}241 242				if (!vringh_notify_enable_user(&vrh))243					continue;244 245				/* Swallow all notifies at once. */246				if (read(to_host[0], buf, sizeof(buf)) < 1)247					break;248 249				vringh_notify_disable_user(&vrh);250				receives++;251				continue;252			}253			if (err != 1)254				errx(1, "vringh_getdesc_user: %i", err);255 256			/* We simply copy bytes. */257			if (riov.used) {258				rlen = vringh_iov_pull_user(&riov, rbuf,259							    sizeof(rbuf));260				if (rlen != 4)261					errx(1, "vringh_iov_pull_user: %i",262					     rlen);263				assert(riov.i == riov.used);264				written = 0;265			} else {266				err = vringh_iov_push_user(&wiov, rbuf, rlen);267				if (err != rlen)268					errx(1, "vringh_iov_push_user: %i",269					     err);270				assert(wiov.i == wiov.used);271				written = err;272			}273		complete:274			xfers++;275 276			err = vringh_complete_user(&vrh, head, written);277			if (err != 0)278				errx(1, "vringh_complete_user: %i", err);279		}280 281		err = vringh_need_notify_user(&vrh);282		if (err < 0)283			errx(1, "vringh_need_notify_user: %i", err);284		if (err) {285			write(to_guest[1], "", 1);286			notifies++;287		}288		wait(&status);289		if (!WIFEXITED(status))290			errx(1, "Child died with signal %i?", WTERMSIG(status));291		if (WEXITSTATUS(status) != 0)292			errx(1, "Child exited %i?", WEXITSTATUS(status));293		printf("Host: notified %lu, pinged %lu\n", notifies, receives);294		return 0;295	} else {296		struct guest_virtio_device gvdev;297		struct virtqueue *vq;298		unsigned int *data;299		struct vring_desc *indirects;300		unsigned int finished = 0;301 302		/* We pass sg[]s pointing into here, but we need RINGSIZE+1 */303		data = guest_map + vring_size(RINGSIZE, ALIGN);304		indirects = (void *)data + (RINGSIZE + 1) * 2 * sizeof(int);305 306		/* We are the guest. */307		munmap(host_map, mapsize);308 309		close(to_guest[1]);310		close(to_host[0]);311 312		gvdev.vdev.features = features;313		INIT_LIST_HEAD(&gvdev.vdev.vqs);314		spin_lock_init(&gvdev.vdev.vqs_list_lock);315		gvdev.to_host_fd = to_host[1];316		gvdev.notifies = 0;317 318		CPU_SET(first_cpu, &cpu_set);319		if (sched_setaffinity(getpid(), sizeof(cpu_set), &cpu_set))320			err(1, "Could not set affinity to cpu %u", first_cpu);321 322		vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &gvdev.vdev, true,323					 false, guest_map,324					 fast_vringh ? no_notify_host325					 : parallel_notify_host,326					 never_callback_guest, "guest vq");327 328		/* Don't kfree indirects. */329		__kfree_ignore_start = indirects;330		__kfree_ignore_end = indirects + RINGSIZE * 6;331 332		while (xfers < NUM_XFERS) {333			struct scatterlist sg[4];334			unsigned int num_sg, len;335			int *dbuf, err;336			bool output = !(xfers % 2);337 338			/* Consume bufs. */339			while ((dbuf = virtqueue_get_buf(vq, &len)) != NULL) {340				if (len == 4)341					assert(*dbuf == finished - 1);342				else if (!fast_vringh)343					assert(*dbuf == finished);344				finished++;345			}346 347			/* Produce a buffer. */348			dbuf = data + (xfers % (RINGSIZE + 1));349 350			if (output)351				*dbuf = xfers;352			else353				*dbuf = -1;354 355			switch ((xfers / sizeof(*dbuf)) % 4) {356			case 0:357				/* Nasty three-element sg list. */358				sg_init_table(sg, num_sg = 3);359				sg_set_buf(&sg[0], (void *)dbuf, 1);360				sg_set_buf(&sg[1], (void *)dbuf + 1, 2);361				sg_set_buf(&sg[2], (void *)dbuf + 3, 1);362				break;363			case 1:364				sg_init_table(sg, num_sg = 2);365				sg_set_buf(&sg[0], (void *)dbuf, 1);366				sg_set_buf(&sg[1], (void *)dbuf + 1, 3);367				break;368			case 2:369				sg_init_table(sg, num_sg = 1);370				sg_set_buf(&sg[0], (void *)dbuf, 4);371				break;372			case 3:373				sg_init_table(sg, num_sg = 4);374				sg_set_buf(&sg[0], (void *)dbuf, 1);375				sg_set_buf(&sg[1], (void *)dbuf + 1, 1);376				sg_set_buf(&sg[2], (void *)dbuf + 2, 1);377				sg_set_buf(&sg[3], (void *)dbuf + 3, 1);378				break;379			}380 381			/* May allocate an indirect, so force it to allocate382			 * user addr */383			__kmalloc_fake = indirects + (xfers % RINGSIZE) * 4;384			if (output)385				err = virtqueue_add_outbuf(vq, sg, num_sg, dbuf,386							   GFP_KERNEL);387			else388				err = virtqueue_add_inbuf(vq, sg, num_sg,389							  dbuf, GFP_KERNEL);390 391			if (err == -ENOSPC) {392				if (!virtqueue_enable_cb_delayed(vq))393					continue;394				/* Swallow all notifies at once. */395				if (read(to_guest[0], buf, sizeof(buf)) < 1)396					break;397				398				receives++;399				virtqueue_disable_cb(vq);400				continue;401			}402 403			if (err)404				errx(1, "virtqueue_add_in/outbuf: %i", err);405 406			xfers++;407			virtqueue_kick(vq);408		}409 410		/* Any extra? */411		while (finished != xfers) {412			int *dbuf;413			unsigned int len;414 415			/* Consume bufs. */416			dbuf = virtqueue_get_buf(vq, &len);417			if (dbuf) {418				if (len == 4)419					assert(*dbuf == finished - 1);420				else421					assert(len == 0);422				finished++;423				continue;424			}425 426			if (!virtqueue_enable_cb_delayed(vq))427				continue;428			if (read(to_guest[0], buf, sizeof(buf)) < 1)429				break;430				431			receives++;432			virtqueue_disable_cb(vq);433		}434 435		printf("Guest: notified %lu, pinged %lu\n",436		       gvdev.notifies, receives);437		vring_del_virtqueue(vq);438		return 0;439	}440}441 442int main(int argc, char *argv[])443{444	struct virtio_device vdev;445	struct virtqueue *vq;446	struct vringh vrh;447	struct scatterlist guest_sg[RINGSIZE], *sgs[2];448	struct iovec host_riov[2], host_wiov[2];449	struct vringh_iov riov, wiov;450	struct vring_used_elem used[RINGSIZE];451	char buf[28];452	u16 head;453	int err;454	unsigned i;455	void *ret;456	bool (*getrange)(struct vringh *vrh, u64 addr, struct vringh_range *r);457	bool fast_vringh = false, parallel = false;458 459	getrange = getrange_iov;460	vdev.features = 0;461	INIT_LIST_HEAD(&vdev.vqs);462	spin_lock_init(&vdev.vqs_list_lock);463 464	while (argv[1]) {465		if (strcmp(argv[1], "--indirect") == 0)466			__virtio_set_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC);467		else if (strcmp(argv[1], "--eventidx") == 0)468			__virtio_set_bit(&vdev, VIRTIO_RING_F_EVENT_IDX);469		else if (strcmp(argv[1], "--virtio-1") == 0)470			__virtio_set_bit(&vdev, VIRTIO_F_VERSION_1);471		else if (strcmp(argv[1], "--slow-range") == 0)472			getrange = getrange_slow;473		else if (strcmp(argv[1], "--fast-vringh") == 0)474			fast_vringh = true;475		else if (strcmp(argv[1], "--parallel") == 0)476			parallel = true;477		else478			errx(1, "Unknown arg %s", argv[1]);479		argv++;480	}481 482	if (parallel)483		return parallel_test(vdev.features, getrange, fast_vringh);484 485	if (posix_memalign(&__user_addr_min, PAGE_SIZE, USER_MEM) != 0)486		abort();487	__user_addr_max = __user_addr_min + USER_MEM;488	memset(__user_addr_min, 0, vring_size(RINGSIZE, ALIGN));489 490	/* Set up guest side. */491	vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &vdev, true, false,492				 __user_addr_min,493				 never_notify_host, never_callback_guest,494				 "guest vq");495 496	/* Set up host side. */497	vring_init(&vrh.vring, RINGSIZE, __user_addr_min, ALIGN);498	vringh_init_user(&vrh, vdev.features, RINGSIZE, true,499			 vrh.vring.desc, vrh.vring.avail, vrh.vring.used);500 501	/* No descriptor to get yet... */502	err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);503	if (err != 0)504		errx(1, "vringh_getdesc_user: %i", err);505 506	/* Guest puts in a descriptor. */507	memcpy(__user_addr_max - 1, "a", 1);508	sg_init_table(guest_sg, 1);509	sg_set_buf(&guest_sg[0], __user_addr_max - 1, 1);510	sg_init_table(guest_sg+1, 1);511	sg_set_buf(&guest_sg[1], __user_addr_max - 3, 2);512	sgs[0] = &guest_sg[0];513	sgs[1] = &guest_sg[1];514 515	/* May allocate an indirect, so force it to allocate user addr */516	__kmalloc_fake = __user_addr_min + vring_size(RINGSIZE, ALIGN);517	err = virtqueue_add_sgs(vq, sgs, 1, 1, &err, GFP_KERNEL);518	if (err)519		errx(1, "virtqueue_add_sgs: %i", err);520	__kmalloc_fake = NULL;521 522	/* Host retrieves it. */523	vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov));524	vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov));525 526	err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);527	if (err != 1)528		errx(1, "vringh_getdesc_user: %i", err);529 530	assert(riov.used == 1);531	assert(riov.iov[0].iov_base == __user_addr_max - 1);532	assert(riov.iov[0].iov_len == 1);533	if (getrange != getrange_slow) {534		assert(wiov.used == 1);535		assert(wiov.iov[0].iov_base == __user_addr_max - 3);536		assert(wiov.iov[0].iov_len == 2);537	} else {538		assert(wiov.used == 2);539		assert(wiov.iov[0].iov_base == __user_addr_max - 3);540		assert(wiov.iov[0].iov_len == 1);541		assert(wiov.iov[1].iov_base == __user_addr_max - 2);542		assert(wiov.iov[1].iov_len == 1);543	}544 545	err = vringh_iov_pull_user(&riov, buf, 5);546	if (err != 1)547		errx(1, "vringh_iov_pull_user: %i", err);548	assert(buf[0] == 'a');549	assert(riov.i == 1);550	assert(vringh_iov_pull_user(&riov, buf, 5) == 0);551 552	memcpy(buf, "bcdef", 5);553	err = vringh_iov_push_user(&wiov, buf, 5);554	if (err != 2)555		errx(1, "vringh_iov_push_user: %i", err);556	assert(memcmp(__user_addr_max - 3, "bc", 2) == 0);557	assert(wiov.i == wiov.used);558	assert(vringh_iov_push_user(&wiov, buf, 5) == 0);559 560	/* Host is done. */561	err = vringh_complete_user(&vrh, head, err);562	if (err != 0)563		errx(1, "vringh_complete_user: %i", err);564 565	/* Guest should see used token now. */566	__kfree_ignore_start = __user_addr_min + vring_size(RINGSIZE, ALIGN);567	__kfree_ignore_end = __kfree_ignore_start + 1;568	ret = virtqueue_get_buf(vq, &i);569	if (ret != &err)570		errx(1, "virtqueue_get_buf: %p", ret);571	assert(i == 2);572 573	/* Guest puts in a huge descriptor. */574	sg_init_table(guest_sg, RINGSIZE);575	for (i = 0; i < RINGSIZE; i++) {576		sg_set_buf(&guest_sg[i],577			   __user_addr_max - USER_MEM/4, USER_MEM/4);578	}579 580	/* Fill contents with recognisable garbage. */581	for (i = 0; i < USER_MEM/4; i++)582		((char *)__user_addr_max - USER_MEM/4)[i] = i;583 584	/* This will allocate an indirect, so force it to allocate user addr */585	__kmalloc_fake = __user_addr_min + vring_size(RINGSIZE, ALIGN);586	err = virtqueue_add_outbuf(vq, guest_sg, RINGSIZE, &err, GFP_KERNEL);587	if (err)588		errx(1, "virtqueue_add_outbuf (large): %i", err);589	__kmalloc_fake = NULL;590 591	/* Host picks it up (allocates new iov). */592	vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov));593	vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov));594 595	err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);596	if (err != 1)597		errx(1, "vringh_getdesc_user: %i", err);598 599	assert(riov.max_num & VRINGH_IOV_ALLOCATED);600	assert(riov.iov != host_riov);601	if (getrange != getrange_slow)602		assert(riov.used == RINGSIZE);603	else604		assert(riov.used == RINGSIZE * USER_MEM/4);605 606	assert(!(wiov.max_num & VRINGH_IOV_ALLOCATED));607	assert(wiov.used == 0);608 609	/* Pull data back out (in odd chunks), should be as expected. */610	for (i = 0; i < RINGSIZE * USER_MEM/4; i += 3) {611		err = vringh_iov_pull_user(&riov, buf, 3);612		if (err != 3 && i + err != RINGSIZE * USER_MEM/4)613			errx(1, "vringh_iov_pull_user large: %i", err);614		assert(buf[0] == (char)i);615		assert(err < 2 || buf[1] == (char)(i + 1));616		assert(err < 3 || buf[2] == (char)(i + 2));617	}618	assert(riov.i == riov.used);619	vringh_iov_cleanup(&riov);620	vringh_iov_cleanup(&wiov);621 622	/* Complete using multi interface, just because we can. */623	used[0].id = head;624	used[0].len = 0;625	err = vringh_complete_multi_user(&vrh, used, 1);626	if (err)627		errx(1, "vringh_complete_multi_user(1): %i", err);628 629	/* Free up those descriptors. */630	ret = virtqueue_get_buf(vq, &i);631	if (ret != &err)632		errx(1, "virtqueue_get_buf: %p", ret);633 634	/* Add lots of descriptors. */635	sg_init_table(guest_sg, 1);636	sg_set_buf(&guest_sg[0], __user_addr_max - 1, 1);637	for (i = 0; i < RINGSIZE; i++) {638		err = virtqueue_add_outbuf(vq, guest_sg, 1, &err, GFP_KERNEL);639		if (err)640			errx(1, "virtqueue_add_outbuf (multiple): %i", err);641	}642 643	/* Now get many, and consume them all at once. */644	vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov));645	vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov));646 647	for (i = 0; i < RINGSIZE; i++) {648		err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);649		if (err != 1)650			errx(1, "vringh_getdesc_user: %i", err);651		used[i].id = head;652		used[i].len = 0;653	}654	/* Make sure it wraps around ring, to test! */655	assert(vrh.vring.used->idx % RINGSIZE != 0);656	err = vringh_complete_multi_user(&vrh, used, RINGSIZE);657	if (err)658		errx(1, "vringh_complete_multi_user: %i", err);659 660	/* Free those buffers. */661	for (i = 0; i < RINGSIZE; i++) {662		unsigned len;663		assert(virtqueue_get_buf(vq, &len) != NULL);664	}665 666	/* Test weird (but legal!) indirect. */667	if (__virtio_test_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC)) {668		char *data = __user_addr_max - USER_MEM/4;669		struct vring_desc *d = __user_addr_max - USER_MEM/2;670		struct vring vring;671 672		/* Force creation of direct, which we modify. */673		__virtio_clear_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC);674		vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &vdev, true,675					 false, __user_addr_min,676					 never_notify_host,677					 never_callback_guest,678					 "guest vq");679 680		sg_init_table(guest_sg, 4);681		sg_set_buf(&guest_sg[0], d, sizeof(*d)*2);682		sg_set_buf(&guest_sg[1], d + 2, sizeof(*d)*1);683		sg_set_buf(&guest_sg[2], data + 6, 4);684		sg_set_buf(&guest_sg[3], d + 3, sizeof(*d)*3);685 686		err = virtqueue_add_outbuf(vq, guest_sg, 4, &err, GFP_KERNEL);687		if (err)688			errx(1, "virtqueue_add_outbuf (indirect): %i", err);689 690		vring_init(&vring, RINGSIZE, __user_addr_min, ALIGN);691 692		/* They're used in order, but double-check... */693		assert(vring.desc[0].addr == (unsigned long)d);694		assert(vring.desc[1].addr == (unsigned long)(d+2));695		assert(vring.desc[2].addr == (unsigned long)data + 6);696		assert(vring.desc[3].addr == (unsigned long)(d+3));697		vring.desc[0].flags |= VRING_DESC_F_INDIRECT;698		vring.desc[1].flags |= VRING_DESC_F_INDIRECT;699		vring.desc[3].flags |= VRING_DESC_F_INDIRECT;700 701		/* First indirect */702		d[0].addr = (unsigned long)data;703		d[0].len = 1;704		d[0].flags = VRING_DESC_F_NEXT;705		d[0].next = 1;706		d[1].addr = (unsigned long)data + 1;707		d[1].len = 2;708		d[1].flags = 0;709 710		/* Second indirect */711		d[2].addr = (unsigned long)data + 3;712		d[2].len = 3;713		d[2].flags = 0;714 715		/* Third indirect */716		d[3].addr = (unsigned long)data + 10;717		d[3].len = 5;718		d[3].flags = VRING_DESC_F_NEXT;719		d[3].next = 1;720		d[4].addr = (unsigned long)data + 15;721		d[4].len = 6;722		d[4].flags = VRING_DESC_F_NEXT;723		d[4].next = 2;724		d[5].addr = (unsigned long)data + 21;725		d[5].len = 7;726		d[5].flags = 0;727 728		/* Host picks it up (allocates new iov). */729		vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov));730		vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov));731 732		err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);733		if (err != 1)734			errx(1, "vringh_getdesc_user: %i", err);735 736		if (head != 0)737			errx(1, "vringh_getdesc_user: head %i not 0", head);738 739		assert(riov.max_num & VRINGH_IOV_ALLOCATED);740		if (getrange != getrange_slow)741			assert(riov.used == 7);742		else743			assert(riov.used == 28);744		err = vringh_iov_pull_user(&riov, buf, 29);745		assert(err == 28);746 747		/* Data should be linear. */748		for (i = 0; i < err; i++)749			assert(buf[i] == i);750		vringh_iov_cleanup(&riov);751	}752 753	/* Don't leak memory... */754	vring_del_virtqueue(vq);755	free(__user_addr_min);756 757	return 0;758}759