[qemu.git] / block / blkverify.c

/*
 * Block protocol for block driver correctness testing
 *
 * Copyright (C) 2010 IBM, Corp.
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or later.
 * See the COPYING file in the top-level directory.
 */

#include <stdarg.h>
#include "qemu_socket.h" /* for EINPROGRESS on Windows */
#include "block_int.h"

typedef struct {
    BlockDriverState *test_file;
} BDRVBlkverifyState;

typedef struct BlkverifyAIOCB BlkverifyAIOCB;
struct BlkverifyAIOCB {
    BlockDriverAIOCB common;
    QEMUBH *bh;

    /* Request metadata */
    bool is_write;
    int64_t sector_num;
    int nb_sectors;

    int ret;                    /* first completed request's result */
    unsigned int done;          /* completion counter */
    bool *finished;             /* completion signal for cancel */

    QEMUIOVector *qiov;         /* user I/O vector */
    QEMUIOVector raw_qiov;      /* cloned I/O vector for raw file */
    void *buf;                  /* buffer for raw file I/O */

    void (*verify)(BlkverifyAIOCB *acb);
};

static void blkverify_aio_cancel(BlockDriverAIOCB *blockacb)
{
    BlkverifyAIOCB *acb = (BlkverifyAIOCB *)blockacb;
    bool finished = false;

    /* Wait until request completes, invokes its callback, and frees itself */
    acb->finished = &finished;
    while (!finished) {
        qemu_aio_wait();
    }
}

static AIOPool blkverify_aio_pool = {
    .aiocb_size         = sizeof(BlkverifyAIOCB),
    .cancel             = blkverify_aio_cancel,
};

static void GCC_FMT_ATTR(2, 3) blkverify_err(BlkverifyAIOCB *acb,
                                             const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    fprintf(stderr, "blkverify: %s sector_num=%" PRId64 " nb_sectors=%d ",
            acb->is_write ? "write" : "read", acb->sector_num,
            acb->nb_sectors);
    vfprintf(stderr, fmt, ap);
    fprintf(stderr, "\n");
    va_end(ap);
    exit(1);
}

/* Valid blkverify filenames look like blkverify:path/to/raw_image:path/to/image */
static int blkverify_open(BlockDriverState *bs, const char *filename, int flags)
{
    BDRVBlkverifyState *s = bs->opaque;
    int ret;
    char *raw, *c;

    /* Parse the blkverify: prefix */
    if (strncmp(filename, "blkverify:", strlen("blkverify:"))) {
        return -EINVAL;
    }
    filename += strlen("blkverify:");

    /* Parse the raw image filename */
    c = strchr(filename, ':');
    if (c == NULL) {
        return -EINVAL;
    }

    raw = strdup(filename);
    raw[c - filename] = '\0';
    ret = bdrv_file_open(&bs->file, raw, flags);
    free(raw);
    if (ret < 0) {
        return ret;
    }
    filename = c + 1;

    /* Open the test file */
    s->test_file = bdrv_new("");
    ret = bdrv_open(s->test_file, filename, flags, NULL);
    if (ret < 0) {
        bdrv_delete(s->test_file);
        s->test_file = NULL;
        return ret;
    }

    return 0;
}

static void blkverify_close(BlockDriverState *bs)
{
    BDRVBlkverifyState *s = bs->opaque;

    bdrv_delete(s->test_file);
    s->test_file = NULL;
}

static int blkverify_flush(BlockDriverState *bs)
{
    BDRVBlkverifyState *s = bs->opaque;

    /* Only flush test file, the raw file is not important */
    return bdrv_flush(s->test_file);
}

static int64_t blkverify_getlength(BlockDriverState *bs)
{
    BDRVBlkverifyState *s = bs->opaque;

    return bdrv_getlength(s->test_file);
}

/**
 * Check that I/O vector contents are identical
 *
 * @a:          I/O vector
 * @b:          I/O vector
 * @ret:        Offset to first mismatching byte or -1 if match
 */
static ssize_t blkverify_iovec_compare(QEMUIOVector *a, QEMUIOVector *b)
{
    int i;
    ssize_t offset = 0;

    assert(a->niov == b->niov);
    for (i = 0; i < a->niov; i++) {
        size_t len = 0;
        uint8_t *p = (uint8_t *)a->iov[i].iov_base;
        uint8_t *q = (uint8_t *)b->iov[i].iov_base;

        assert(a->iov[i].iov_len == b->iov[i].iov_len);
        while (len < a->iov[i].iov_len && *p++ == *q++) {
            len++;
        }

        offset += len;

        if (len != a->iov[i].iov_len) {
            return offset;
        }
    }
    return -1;
}

typedef struct {
    int src_index;
    struct iovec *src_iov;
    void *dest_base;
} IOVectorSortElem;

static int sortelem_cmp_src_base(const void *a, const void *b)
{
    const IOVectorSortElem *elem_a = a;
    const IOVectorSortElem *elem_b = b;

    /* Don't overflow */
    if (elem_a->src_iov->iov_base < elem_b->src_iov->iov_base) {
        return -1;
    } else if (elem_a->src_iov->iov_base > elem_b->src_iov->iov_base) {
        return 1;
    } else {
        return 0;
    }
}

static int sortelem_cmp_src_index(const void *a, const void *b)
{
    const IOVectorSortElem *elem_a = a;
    const IOVectorSortElem *elem_b = b;

    return elem_a->src_index - elem_b->src_index;
}

/**
 * Copy contents of I/O vector
 *
 * The relative relationships of overlapping iovecs are preserved.  This is
 * necessary to ensure identical semantics in the cloned I/O vector.
 */
static void blkverify_iovec_clone(QEMUIOVector *dest, const QEMUIOVector *src,
                                  void *buf)
{
    IOVectorSortElem sortelems[src->niov];
    void *last_end;
    int i;

    /* Sort by source iovecs by base address */
    for (i = 0; i < src->niov; i++) {
        sortelems[i].src_index = i;
        sortelems[i].src_iov = &src->iov[i];
    }
    qsort(sortelems, src->niov, sizeof(sortelems[0]), sortelem_cmp_src_base);

    /* Allocate buffer space taking into account overlapping iovecs */
    last_end = NULL;
    for (i = 0; i < src->niov; i++) {
        struct iovec *cur = sortelems[i].src_iov;
        ptrdiff_t rewind = 0;

        /* Detect overlap */
        if (last_end && last_end > cur->iov_base) {
            rewind = last_end - cur->iov_base;
        }

        sortelems[i].dest_base = buf - rewind;
        buf += cur->iov_len - MIN(rewind, cur->iov_len);
        last_end = MAX(cur->iov_base + cur->iov_len, last_end);
    }

    /* Sort by source iovec index and build destination iovec */
    qsort(sortelems, src->niov, sizeof(sortelems[0]), sortelem_cmp_src_index);
    for (i = 0; i < src->niov; i++) {
        qemu_iovec_add(dest, sortelems[i].dest_base, src->iov[i].iov_len);
    }
}

static BlkverifyAIOCB *blkverify_aio_get(BlockDriverState *bs, bool is_write,
                                         int64_t sector_num, QEMUIOVector *qiov,
                                         int nb_sectors,
                                         BlockDriverCompletionFunc *cb,
                                         void *opaque)
{
    BlkverifyAIOCB *acb = qemu_aio_get(&blkverify_aio_pool, bs, cb, opaque);

    acb->bh = NULL;
    acb->is_write = is_write;
    acb->sector_num = sector_num;
    acb->nb_sectors = nb_sectors;
    acb->ret = -EINPROGRESS;
    acb->done = 0;
    acb->qiov = qiov;
    acb->buf = NULL;
    acb->verify = NULL;
    acb->finished = NULL;
    return acb;
}

static void blkverify_aio_bh(void *opaque)
{
    BlkverifyAIOCB *acb = opaque;

    qemu_bh_delete(acb->bh);
    if (acb->buf) {
        qemu_iovec_destroy(&acb->raw_qiov);
        qemu_vfree(acb->buf);
    }
    acb->common.cb(acb->common.opaque, acb->ret);
    if (acb->finished) {
        *acb->finished = true;
    }
    qemu_aio_release(acb);
}

static void blkverify_aio_cb(void *opaque, int ret)
{
    BlkverifyAIOCB *acb = opaque;

    switch (++acb->done) {
    case 1:
        acb->ret = ret;
        break;

    case 2:
        if (acb->ret != ret) {
            blkverify_err(acb, "return value mismatch %d != %d", acb->ret, ret);
        }

        if (acb->verify) {
            acb->verify(acb);
        }

        acb->bh = qemu_bh_new(blkverify_aio_bh, acb);
        qemu_bh_schedule(acb->bh);
        break;
    }
}

static void blkverify_verify_readv(BlkverifyAIOCB *acb)
{
    ssize_t offset = blkverify_iovec_compare(acb->qiov, &acb->raw_qiov);
    if (offset != -1) {
        blkverify_err(acb, "contents mismatch in sector %" PRId64,
                      acb->sector_num + (int64_t)(offset / BDRV_SECTOR_SIZE));
    }
}

static BlockDriverAIOCB *blkverify_aio_readv(BlockDriverState *bs,
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
        BlockDriverCompletionFunc *cb, void *opaque)
{
    BDRVBlkverifyState *s = bs->opaque;
    BlkverifyAIOCB *acb = blkverify_aio_get(bs, false, sector_num, qiov,
                                            nb_sectors, cb, opaque);

    acb->verify = blkverify_verify_readv;
    acb->buf = qemu_blockalign(bs->file, qiov->size);
    qemu_iovec_init(&acb->raw_qiov, acb->qiov->niov);
    blkverify_iovec_clone(&acb->raw_qiov, qiov, acb->buf);

    if (!bdrv_aio_readv(s->test_file, sector_num, qiov, nb_sectors,
                        blkverify_aio_cb, acb)) {
        blkverify_aio_cb(acb, -EIO);
    }
    if (!bdrv_aio_readv(bs->file, sector_num, &acb->raw_qiov, nb_sectors,
                        blkverify_aio_cb, acb)) {
        blkverify_aio_cb(acb, -EIO);
    }
    return &acb->common;
}

static BlockDriverAIOCB *blkverify_aio_writev(BlockDriverState *bs,
        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
        BlockDriverCompletionFunc *cb, void *opaque)
{
    BDRVBlkverifyState *s = bs->opaque;
    BlkverifyAIOCB *acb = blkverify_aio_get(bs, true, sector_num, qiov,
                                            nb_sectors, cb, opaque);

    if (!bdrv_aio_writev(s->test_file, sector_num, qiov, nb_sectors,
                         blkverify_aio_cb, acb)) {
        blkverify_aio_cb(acb, -EIO);
    }
    if (!bdrv_aio_writev(bs->file, sector_num, qiov, nb_sectors,
                         blkverify_aio_cb, acb)) {
        blkverify_aio_cb(acb, -EIO);
    }
    return &acb->common;
}

static BlockDriverAIOCB *blkverify_aio_flush(BlockDriverState *bs,
                                             BlockDriverCompletionFunc *cb,
                                             void *opaque)
{
    BDRVBlkverifyState *s = bs->opaque;

    /* Only flush test file, the raw file is not important */
    return bdrv_aio_flush(s->test_file, cb, opaque);
}

static BlockDriver bdrv_blkverify = {
    .format_name        = "blkverify",
    .protocol_name      = "blkverify",

    .instance_size      = sizeof(BDRVBlkverifyState),

    .bdrv_getlength     = blkverify_getlength,

    .bdrv_file_open     = blkverify_open,
    .bdrv_close         = blkverify_close,
    .bdrv_flush         = blkverify_flush,

    .bdrv_aio_readv     = blkverify_aio_readv,
    .bdrv_aio_writev    = blkverify_aio_writev,
    .bdrv_aio_flush     = blkverify_aio_flush,
};

static void bdrv_blkverify_init(void)
{
    bdrv_register(&bdrv_blkverify);
}

block_init(bdrv_blkverify_init);
Commit	Line	Data
d9d33417 SH	1	/*
	2	* Block protocol for block driver correctness testing
	3	*
	4	* Copyright (C) 2010 IBM, Corp.
	5	*
	6	* This work is licensed under the terms of the GNU GPL, version 2 or later.
	7	* See the COPYING file in the top-level directory.
	8	*/
	9
	10	#include <stdarg.h>
	11	#include "qemu_socket.h" /* for EINPROGRESS on Windows */
	12	#include "block_int.h"
	13
	14	typedef struct {
	15	BlockDriverState *test_file;
	16	} BDRVBlkverifyState;
	17
	18	typedef struct BlkverifyAIOCB BlkverifyAIOCB;
	19	struct BlkverifyAIOCB {
	20	BlockDriverAIOCB common;
	21	QEMUBH *bh;
	22
	23	/* Request metadata */
	24	bool is_write;
	25	int64_t sector_num;
	26	int nb_sectors;
	27
	28	int ret; /* first completed request's result */
	29	unsigned int done; /* completion counter */
	30	bool finished; / completion signal for cancel */
	31
	32	QEMUIOVector qiov; / user I/O vector */
	33	QEMUIOVector raw_qiov; /* cloned I/O vector for raw file */
	34	void buf; / buffer for raw file I/O */
	35
	36	void (verify)(BlkverifyAIOCB acb);
	37	};
	38
	39	static void blkverify_aio_cancel(BlockDriverAIOCB *blockacb)
	40	{
	41	BlkverifyAIOCB acb = (BlkverifyAIOCB )blockacb;
	42	bool finished = false;
	43
	44	/* Wait until request completes, invokes its callback, and frees itself */
	45	acb->finished = &finished;
	46	while (!finished) {
	47	qemu_aio_wait();
	48	}
	49	}
	50
	51	static AIOPool blkverify_aio_pool = {
	52	.aiocb_size = sizeof(BlkverifyAIOCB),
	53	.cancel = blkverify_aio_cancel,
	54	};
	55
a77cffe7 SW	56	static void GCC_FMT_ATTR(2, 3) blkverify_err(BlkverifyAIOCB *acb,
a77cffe7 SW	57	const char *fmt, ...)
d9d33417 SH	58	{
	59	va_list ap;
	60
	61	va_start(ap, fmt);
687db4ed	62	fprintf(stderr, "blkverify: %s sector_num=%" PRId64 " nb_sectors=%d ",
d9d33417 SH	63	acb->is_write ? "write" : "read", acb->sector_num,
	64	acb->nb_sectors);
	65	vfprintf(stderr, fmt, ap);
	66	fprintf(stderr, "\n");
	67	va_end(ap);
	68	exit(1);
	69	}
	70
	71	/* Valid blkverify filenames look like blkverify:path/to/raw_image:path/to/image */
	72	static int blkverify_open(BlockDriverState bs, const char filename, int flags)
	73	{
	74	BDRVBlkverifyState *s = bs->opaque;
	75	int ret;
	76	char raw, c;
	77
	78	/* Parse the blkverify: prefix */
	79	if (strncmp(filename, "blkverify:", strlen("blkverify:"))) {
	80	return -EINVAL;
	81	}
	82	filename += strlen("blkverify:");
	83
	84	/* Parse the raw image filename */
	85	c = strchr(filename, ':');
	86	if (c == NULL) {
	87	return -EINVAL;
	88	}
	89
	90	raw = strdup(filename);
	91	raw[c - filename] = '\0';
	92	ret = bdrv_file_open(&bs->file, raw, flags);
	93	free(raw);
	94	if (ret < 0) {
	95	return ret;
	96	}
	97	filename = c + 1;
	98
	99	/* Open the test file */
	100	s->test_file = bdrv_new("");
	101	ret = bdrv_open(s->test_file, filename, flags, NULL);
	102	if (ret < 0) {
	103	bdrv_delete(s->test_file);
	104	s->test_file = NULL;
	105	return ret;
	106	}
	107
	108	return 0;
	109	}
	110
	111	static void blkverify_close(BlockDriverState *bs)
	112	{
	113	BDRVBlkverifyState *s = bs->opaque;
	114
	115	bdrv_delete(s->test_file);
	116	s->test_file = NULL;
	117	}
	118
205ef796	119	static int blkverify_flush(BlockDriverState *bs)
d9d33417 SH	120	{
	121	BDRVBlkverifyState *s = bs->opaque;
	122
	123	/* Only flush test file, the raw file is not important */
205ef796	124	return bdrv_flush(s->test_file);
d9d33417 SH	125	}
	126
	127	static int64_t blkverify_getlength(BlockDriverState *bs)
	128	{
	129	BDRVBlkverifyState *s = bs->opaque;
	130
	131	return bdrv_getlength(s->test_file);
	132	}
	133
	134	/**
	135	* Check that I/O vector contents are identical
	136	*
	137	* @a: I/O vector
	138	* @b: I/O vector
	139	* @ret: Offset to first mismatching byte or -1 if match
	140	*/
	141	static ssize_t blkverify_iovec_compare(QEMUIOVector a, QEMUIOVector b)
	142	{
	143	int i;
	144	ssize_t offset = 0;
	145
	146	assert(a->niov == b->niov);
	147	for (i = 0; i < a->niov; i++) {
	148	size_t len = 0;
	149	uint8_t p = (uint8_t )a->iov[i].iov_base;
	150	uint8_t q = (uint8_t )b->iov[i].iov_base;
	151
	152	assert(a->iov[i].iov_len == b->iov[i].iov_len);
	153	while (len < a->iov[i].iov_len && p++ == q++) {
	154	len++;
	155	}
	156
	157	offset += len;
	158
	159	if (len != a->iov[i].iov_len) {
	160	return offset;
	161	}
	162	}
	163	return -1;
	164	}
	165
	166	typedef struct {
	167	int src_index;
	168	struct iovec *src_iov;
	169	void *dest_base;
	170	} IOVectorSortElem;
	171
	172	static int sortelem_cmp_src_base(const void a, const void b)
	173	{
	174	const IOVectorSortElem *elem_a = a;
	175	const IOVectorSortElem *elem_b = b;
	176
	177	/* Don't overflow */
	178	if (elem_a->src_iov->iov_base < elem_b->src_iov->iov_base) {
	179	return -1;
	180	} else if (elem_a->src_iov->iov_base > elem_b->src_iov->iov_base) {
	181	return 1;
	182	} else {
	183	return 0;
	184	}
	185	}
	186
	187	static int sortelem_cmp_src_index(const void a, const void b)
	188	{
189	const IOVectorSortElem *elem_a = a;
190	const IOVectorSortElem *elem_b = b;
191
192	return elem_a->src_index - elem_b->src_index;
193	}
194
195	/**
196	* Copy contents of I/O vector
197	*
198	* The relative relationships of overlapping iovecs are preserved. This is
199	* necessary to ensure identical semantics in the cloned I/O vector.
200	*/
201	static void blkverify_iovec_clone(QEMUIOVector dest, const QEMUIOVector src,
202	void *buf)
203	{
204	IOVectorSortElem sortelems[src->niov];
205	void *last_end;
206	int i;
207
208	/* Sort by source iovecs by base address */
209	for (i = 0; i < src->niov; i++) {
210	sortelems[i].src_index = i;
211	sortelems[i].src_iov = &src->iov[i];
212	}
213	qsort(sortelems, src->niov, sizeof(sortelems[0]), sortelem_cmp_src_base);
214
215	/* Allocate buffer space taking into account overlapping iovecs */
216	last_end = NULL;
217	for (i = 0; i < src->niov; i++) {
218	struct iovec *cur = sortelems[i].src_iov;
219	ptrdiff_t rewind = 0;
220
221	/* Detect overlap */
222	if (last_end && last_end > cur->iov_base) {
223	rewind = last_end - cur->iov_base;
224	}
225
226	sortelems[i].dest_base = buf - rewind;
227	buf += cur->iov_len - MIN(rewind, cur->iov_len);
228	last_end = MAX(cur->iov_base + cur->iov_len, last_end);
229	}
230
231	/* Sort by source iovec index and build destination iovec */
232	qsort(sortelems, src->niov, sizeof(sortelems[0]), sortelem_cmp_src_index);
233	for (i = 0; i < src->niov; i++) {
234	qemu_iovec_add(dest, sortelems[i].dest_base, src->iov[i].iov_len);
235	}
236	}
237
238	static BlkverifyAIOCB blkverify_aio_get(BlockDriverState bs, bool is_write,
239	int64_t sector_num, QEMUIOVector *qiov,
240	int nb_sectors,
241	BlockDriverCompletionFunc *cb,
242	void *opaque)
243	{
244	BlkverifyAIOCB *acb = qemu_aio_get(&blkverify_aio_pool, bs, cb, opaque);
245
246	acb->bh = NULL;
247	acb->is_write = is_write;
248	acb->sector_num = sector_num;
249	acb->nb_sectors = nb_sectors;
250	acb->ret = -EINPROGRESS;
251	acb->done = 0;
252	acb->qiov = qiov;
253	acb->buf = NULL;
254	acb->verify = NULL;
255	acb->finished = NULL;
256	return acb;
257	}
258
259	static void blkverify_aio_bh(void *opaque)
260	{
261	BlkverifyAIOCB *acb = opaque;
262
263	qemu_bh_delete(acb->bh);
264	if (acb->buf) {
265	qemu_iovec_destroy(&acb->raw_qiov);
266	qemu_vfree(acb->buf);
267	}
268	acb->common.cb(acb->common.opaque, acb->ret);
269	if (acb->finished) {
270	*acb->finished = true;
271	}
272	qemu_aio_release(acb);
273	}
274
275	static void blkverify_aio_cb(void *opaque, int ret)
276	{
277	BlkverifyAIOCB *acb = opaque;
278
279	switch (++acb->done) {
280	case 1:
281	acb->ret = ret;
282	break;
283
284	case 2:
285	if (acb->ret != ret) {
286	blkverify_err(acb, "return value mismatch %d != %d", acb->ret, ret);
287	}
288
289	if (acb->verify) {
290	acb->verify(acb);
291	}
292
293	acb->bh = qemu_bh_new(blkverify_aio_bh, acb);
294	qemu_bh_schedule(acb->bh);
295	break;
296	}
297	}
298
299	static void blkverify_verify_readv(BlkverifyAIOCB *acb)
300	{
301	ssize_t offset = blkverify_iovec_compare(acb->qiov, &acb->raw_qiov);
302	if (offset != -1) {
a3133586 BS	303	blkverify_err(acb, "contents mismatch in sector %" PRId64,
a3133586 BS	304	acb->sector_num + (int64_t)(offset / BDRV_SECTOR_SIZE));
d9d33417 SH	305	}
	306	}
	307
	308	static BlockDriverAIOCB blkverify_aio_readv(BlockDriverState bs,
	309	int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
	310	BlockDriverCompletionFunc cb, void opaque)
	311	{
	312	BDRVBlkverifyState *s = bs->opaque;
	313	BlkverifyAIOCB *acb = blkverify_aio_get(bs, false, sector_num, qiov,
	314	nb_sectors, cb, opaque);
	315
	316	acb->verify = blkverify_verify_readv;
	317	acb->buf = qemu_blockalign(bs->file, qiov->size);
	318	qemu_iovec_init(&acb->raw_qiov, acb->qiov->niov);
	319	blkverify_iovec_clone(&acb->raw_qiov, qiov, acb->buf);
	320
	321	if (!bdrv_aio_readv(s->test_file, sector_num, qiov, nb_sectors,
	322	blkverify_aio_cb, acb)) {
	323	blkverify_aio_cb(acb, -EIO);
	324	}
	325	if (!bdrv_aio_readv(bs->file, sector_num, &acb->raw_qiov, nb_sectors,
	326	blkverify_aio_cb, acb)) {
	327	blkverify_aio_cb(acb, -EIO);
	328	}
	329	return &acb->common;
	330	}
	331
	332	static BlockDriverAIOCB blkverify_aio_writev(BlockDriverState bs,
	333	int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
	334	BlockDriverCompletionFunc cb, void opaque)
	335	{
	336	BDRVBlkverifyState *s = bs->opaque;
	337	BlkverifyAIOCB *acb = blkverify_aio_get(bs, true, sector_num, qiov,
	338	nb_sectors, cb, opaque);
	339
	340	if (!bdrv_aio_writev(s->test_file, sector_num, qiov, nb_sectors,
	341	blkverify_aio_cb, acb)) {
	342	blkverify_aio_cb(acb, -EIO);
	343	}
	344	if (!bdrv_aio_writev(bs->file, sector_num, qiov, nb_sectors,
	345	blkverify_aio_cb, acb)) {
	346	blkverify_aio_cb(acb, -EIO);
	347	}
	348	return &acb->common;
	349	}
	350
	351	static BlockDriverAIOCB blkverify_aio_flush(BlockDriverState bs,
	352	BlockDriverCompletionFunc *cb,
	353	void *opaque)
	354	{
	355	BDRVBlkverifyState *s = bs->opaque;
	356
	357	/* Only flush test file, the raw file is not important */
	358	return bdrv_aio_flush(s->test_file, cb, opaque);
	359	}
	360
	361	static BlockDriver bdrv_blkverify = {
	362	.format_name = "blkverify",
	363	.protocol_name = "blkverify",
	364
	365	.instance_size = sizeof(BDRVBlkverifyState),
	366
	367	.bdrv_getlength = blkverify_getlength,
	368
369	.bdrv_file_open = blkverify_open,
370	.bdrv_close = blkverify_close,
371	.bdrv_flush = blkverify_flush,
372
373	.bdrv_aio_readv = blkverify_aio_readv,
374	.bdrv_aio_writev = blkverify_aio_writev,
375	.bdrv_aio_flush = blkverify_aio_flush,
376	};
377
378	static void bdrv_blkverify_init(void)
379	{
380	bdrv_register(&bdrv_blkverify);
381	}
382
383	block_init(bdrv_blkverify_init);