[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/sockets.h" /* for EINPROGRESS on Windows */
#include "block/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 const AIOCBInfo blkverify_aiocb_info = {
    .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 void blkverify_parse_filename(const char *filename, QDict *options,
                                     Error **errp)
{
    const char *c;
    QString *raw_path;


    /* Parse the blkverify: prefix */
    if (!strstart(filename, "blkverify:", &filename)) {
        error_setg(errp, "File name string must start with 'blkverify:'");
        return;
    }

    /* Parse the raw image filename */
    c = strchr(filename, ':');
    if (c == NULL) {
        error_setg(errp, "blkverify requires raw copy and original image path");
        return;
    }

    /* TODO Implement option pass-through and set raw.filename here */
    raw_path = qstring_from_substr(filename, 0, c - filename - 1);
    qdict_put(options, "x-raw", raw_path);

    /* TODO Allow multi-level nesting and set file.filename here */
    filename = c + 1;
    qdict_put(options, "x-image", qstring_from_str(filename));
}

static QemuOptsList runtime_opts = {
    .name = "blkverify",
    .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
    .desc = {
        {
            .name = "x-raw",
            .type = QEMU_OPT_STRING,
            .help = "[internal use only, will be removed]",
        },
        {
            .name = "x-image",
            .type = QEMU_OPT_STRING,
            .help = "[internal use only, will be removed]",
        },
        { /* end of list */ }
    },
};

static int blkverify_open(BlockDriverState *bs, QDict *options, int flags,
                          Error **errp)
{
    BDRVBlkverifyState *s = bs->opaque;
    QemuOpts *opts;
    Error *local_err = NULL;
    const char *filename, *raw;
    int ret;

    opts = qemu_opts_create_nofail(&runtime_opts);
    qemu_opts_absorb_qdict(opts, options, &local_err);
    if (error_is_set(&local_err)) {
        qerror_report_err(local_err);
        error_free(local_err);
        ret = -EINVAL;
        goto fail;
    }

    /* Parse the raw image filename */
    raw = qemu_opt_get(opts, "x-raw");
    if (raw == NULL) {
        ret = -EINVAL;
        goto fail;
    }

    ret = bdrv_file_open(&bs->file, raw, NULL, flags, &local_err);
    if (ret < 0) {
        qerror_report_err(local_err);
        error_free(local_err);
        goto fail;
    }

    /* Open the test file */
    filename = qemu_opt_get(opts, "x-image");
    if (filename == NULL) {
        ret = -EINVAL;
        goto fail;
    }

    s->test_file = bdrv_new("");
    ret = bdrv_open(s->test_file, filename, NULL, flags, NULL, &local_err);
    if (ret < 0) {
        qerror_report_err(local_err);
        error_free(local_err);
        bdrv_unref(s->test_file);
        s->test_file = NULL;
        goto fail;
    }

    ret = 0;
fail:
    return ret;
}

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

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

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_aiocb_info, 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);

    bdrv_aio_readv(s->test_file, sector_num, qiov, nb_sectors,
                   blkverify_aio_cb, acb);
    bdrv_aio_readv(bs->file, sector_num, &acb->raw_qiov, nb_sectors,
                   blkverify_aio_cb, acb);
    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);

    bdrv_aio_writev(s->test_file, sector_num, qiov, nb_sectors,
                    blkverify_aio_cb, acb);
    bdrv_aio_writev(bs->file, sector_num, qiov, nb_sectors,
                    blkverify_aio_cb, acb);
    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_parse_filename    = blkverify_parse_filename,
    .bdrv_file_open         = blkverify_open,
    .bdrv_close             = blkverify_close,
    .bdrv_getlength         = blkverify_getlength,

    .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>
1de7afc9	11	#include "qemu/sockets.h" /* for EINPROGRESS on Windows */
737e150e	12	#include "block/block_int.h"
d9d33417 SH	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
d7331bed	51	static const AIOCBInfo blkverify_aiocb_info = {
d9d33417 SH	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 */
16c79092 KW	72	static void blkverify_parse_filename(const char filename, QDict options,
16c79092 KW	73	Error **errp)
d9d33417	74	{
16c79092 KW	75	const char *c;
	76	QString *raw_path;
	77
d9d33417 SH	78
d9d33417 SH	79	/* Parse the blkverify: prefix */
16c79092 KW	80	if (!strstart(filename, "blkverify:", &filename)) {
	81	error_setg(errp, "File name string must start with 'blkverify:'");
	82	return;
d9d33417	83	}
d9d33417 SH	84
	85	/* Parse the raw image filename */
	86	c = strchr(filename, ':');
	87	if (c == NULL) {
16c79092 KW	88	error_setg(errp, "blkverify requires raw copy and original image path");
	89	return;
	90	}
	91
	92	/* TODO Implement option pass-through and set raw.filename here */
	93	raw_path = qstring_from_substr(filename, 0, c - filename - 1);
	94	qdict_put(options, "x-raw", raw_path);
	95
	96	/* TODO Allow multi-level nesting and set file.filename here */
	97	filename = c + 1;
	98	qdict_put(options, "x-image", qstring_from_str(filename));
	99	}
	100
	101	static QemuOptsList runtime_opts = {
	102	.name = "blkverify",
	103	.head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
	104	.desc = {
	105	{
	106	.name = "x-raw",
	107	.type = QEMU_OPT_STRING,
	108	.help = "[internal use only, will be removed]",
	109	},
	110	{
	111	.name = "x-image",
	112	.type = QEMU_OPT_STRING,
	113	.help = "[internal use only, will be removed]",
	114	},
	115	{ /* end of list */ }
	116	},
	117	};
	118
015a1036 HR	119	static int blkverify_open(BlockDriverState bs, QDict options, int flags,
015a1036 HR	120	Error **errp)
16c79092 KW	121	{
	122	BDRVBlkverifyState *s = bs->opaque;
	123	QemuOpts *opts;
	124	Error *local_err = NULL;
	125	const char filename, raw;
	126	int ret;
	127
	128	opts = qemu_opts_create_nofail(&runtime_opts);
	129	qemu_opts_absorb_qdict(opts, options, &local_err);
	130	if (error_is_set(&local_err)) {
	131	qerror_report_err(local_err);
	132	error_free(local_err);
	133	ret = -EINVAL;
	134	goto fail;
	135	}
	136
	137	/* Parse the raw image filename */
	138	raw = qemu_opt_get(opts, "x-raw");
	139	if (raw == NULL) {
	140	ret = -EINVAL;
	141	goto fail;
d9d33417 SH	142	}
d9d33417 SH	143
34b5d2c6	144	ret = bdrv_file_open(&bs->file, raw, NULL, flags, &local_err);
d9d33417	145	if (ret < 0) {
34b5d2c6 HR	146	qerror_report_err(local_err);
34b5d2c6 HR	147	error_free(local_err);
16c79092	148	goto fail;
d9d33417	149	}
d9d33417 SH	150
d9d33417 SH	151	/* Open the test file */
16c79092 KW	152	filename = qemu_opt_get(opts, "x-image");
	153	if (filename == NULL) {
	154	ret = -EINVAL;
	155	goto fail;
	156	}
	157
d9d33417	158	s->test_file = bdrv_new("");
34b5d2c6	159	ret = bdrv_open(s->test_file, filename, NULL, flags, NULL, &local_err);
d9d33417	160	if (ret < 0) {
34b5d2c6 HR	161	qerror_report_err(local_err);
34b5d2c6 HR	162	error_free(local_err);
4f6fd349	163	bdrv_unref(s->test_file);
d9d33417	164	s->test_file = NULL;
16c79092	165	goto fail;
d9d33417 SH	166	}
d9d33417 SH	167
16c79092 KW	168	ret = 0;
	169	fail:
	170	return ret;
d9d33417 SH	171	}
	172
	173	static void blkverify_close(BlockDriverState *bs)
	174	{
	175	BDRVBlkverifyState *s = bs->opaque;
	176
4f6fd349	177	bdrv_unref(s->test_file);
d9d33417 SH	178	s->test_file = NULL;
	179	}
	180
d9d33417 SH	181	static int64_t blkverify_getlength(BlockDriverState *bs)
	182	{
	183	BDRVBlkverifyState *s = bs->opaque;
	184
	185	return bdrv_getlength(s->test_file);
	186	}
	187
	188	/**
	189	* Check that I/O vector contents are identical
	190	*
	191	* @a: I/O vector
	192	* @b: I/O vector
	193	* @ret: Offset to first mismatching byte or -1 if match
	194	*/
	195	static ssize_t blkverify_iovec_compare(QEMUIOVector a, QEMUIOVector b)
	196	{
	197	int i;
	198	ssize_t offset = 0;
	199
	200	assert(a->niov == b->niov);
	201	for (i = 0; i < a->niov; i++) {
	202	size_t len = 0;
	203	uint8_t p = (uint8_t )a->iov[i].iov_base;
	204	uint8_t q = (uint8_t )b->iov[i].iov_base;
	205
	206	assert(a->iov[i].iov_len == b->iov[i].iov_len);
	207	while (len < a->iov[i].iov_len && p++ == q++) {
	208	len++;
	209	}
	210
	211	offset += len;
	212
	213	if (len != a->iov[i].iov_len) {
	214	return offset;
	215	}
	216	}
	217	return -1;
	218	}
	219
	220	typedef struct {
	221	int src_index;
	222	struct iovec *src_iov;
	223	void *dest_base;
	224	} IOVectorSortElem;
	225
	226	static int sortelem_cmp_src_base(const void a, const void b)
	227	{
	228	const IOVectorSortElem *elem_a = a;
	229	const IOVectorSortElem *elem_b = b;
	230
	231	/* Don't overflow */
	232	if (elem_a->src_iov->iov_base < elem_b->src_iov->iov_base) {
	233	return -1;
	234	} else if (elem_a->src_iov->iov_base > elem_b->src_iov->iov_base) {
	235	return 1;
	236	} else {
	237	return 0;
	238	}
	239	}
	240
	241	static int sortelem_cmp_src_index(const void a, const void b)
	242	{
	243	const IOVectorSortElem *elem_a = a;
	244	const IOVectorSortElem *elem_b = b;
245
246	return elem_a->src_index - elem_b->src_index;
247	}
248
249	/**
250	* Copy contents of I/O vector
251	*
252	* The relative relationships of overlapping iovecs are preserved. This is
253	* necessary to ensure identical semantics in the cloned I/O vector.
254	*/
255	static void blkverify_iovec_clone(QEMUIOVector dest, const QEMUIOVector src,
256	void *buf)
257	{
258	IOVectorSortElem sortelems[src->niov];
259	void *last_end;
260	int i;
261
262	/* Sort by source iovecs by base address */
263	for (i = 0; i < src->niov; i++) {
264	sortelems[i].src_index = i;
265	sortelems[i].src_iov = &src->iov[i];
266	}
267	qsort(sortelems, src->niov, sizeof(sortelems[0]), sortelem_cmp_src_base);
268
269	/* Allocate buffer space taking into account overlapping iovecs */
270	last_end = NULL;
271	for (i = 0; i < src->niov; i++) {
272	struct iovec *cur = sortelems[i].src_iov;
273	ptrdiff_t rewind = 0;
274
275	/* Detect overlap */
276	if (last_end && last_end > cur->iov_base) {
277	rewind = last_end - cur->iov_base;
278	}
279
280	sortelems[i].dest_base = buf - rewind;
281	buf += cur->iov_len - MIN(rewind, cur->iov_len);
282	last_end = MAX(cur->iov_base + cur->iov_len, last_end);
283	}
284
285	/* Sort by source iovec index and build destination iovec */
286	qsort(sortelems, src->niov, sizeof(sortelems[0]), sortelem_cmp_src_index);
287	for (i = 0; i < src->niov; i++) {
288	qemu_iovec_add(dest, sortelems[i].dest_base, src->iov[i].iov_len);
289	}
290	}
291
292	static BlkverifyAIOCB blkverify_aio_get(BlockDriverState bs, bool is_write,
293	int64_t sector_num, QEMUIOVector *qiov,
294	int nb_sectors,
295	BlockDriverCompletionFunc *cb,
296	void *opaque)
297	{
d7331bed	298	BlkverifyAIOCB *acb = qemu_aio_get(&blkverify_aiocb_info, bs, cb, opaque);
d9d33417 SH	299
	300	acb->bh = NULL;
	301	acb->is_write = is_write;
	302	acb->sector_num = sector_num;
	303	acb->nb_sectors = nb_sectors;
	304	acb->ret = -EINPROGRESS;
	305	acb->done = 0;
	306	acb->qiov = qiov;
	307	acb->buf = NULL;
	308	acb->verify = NULL;
	309	acb->finished = NULL;
	310	return acb;
	311	}
	312
	313	static void blkverify_aio_bh(void *opaque)
	314	{
	315	BlkverifyAIOCB *acb = opaque;
	316
	317	qemu_bh_delete(acb->bh);
	318	if (acb->buf) {
	319	qemu_iovec_destroy(&acb->raw_qiov);
	320	qemu_vfree(acb->buf);
	321	}
	322	acb->common.cb(acb->common.opaque, acb->ret);
	323	if (acb->finished) {
	324	*acb->finished = true;
	325	}
	326	qemu_aio_release(acb);
	327	}
	328
	329	static void blkverify_aio_cb(void *opaque, int ret)
	330	{
	331	BlkverifyAIOCB *acb = opaque;
	332
	333	switch (++acb->done) {
	334	case 1:
	335	acb->ret = ret;
	336	break;
	337
	338	case 2:
	339	if (acb->ret != ret) {
	340	blkverify_err(acb, "return value mismatch %d != %d", acb->ret, ret);
	341	}
	342
	343	if (acb->verify) {
	344	acb->verify(acb);
	345	}
	346
	347	acb->bh = qemu_bh_new(blkverify_aio_bh, acb);
	348	qemu_bh_schedule(acb->bh);
	349	break;
	350	}
	351	}
	352
	353	static void blkverify_verify_readv(BlkverifyAIOCB *acb)
	354	{
	355	ssize_t offset = blkverify_iovec_compare(acb->qiov, &acb->raw_qiov);
	356	if (offset != -1) {
a3133586 BS	357	blkverify_err(acb, "contents mismatch in sector %" PRId64,
a3133586 BS	358	acb->sector_num + (int64_t)(offset / BDRV_SECTOR_SIZE));
d9d33417 SH	359	}
	360	}
	361
	362	static BlockDriverAIOCB blkverify_aio_readv(BlockDriverState bs,
	363	int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
	364	BlockDriverCompletionFunc cb, void opaque)
	365	{
	366	BDRVBlkverifyState *s = bs->opaque;
	367	BlkverifyAIOCB *acb = blkverify_aio_get(bs, false, sector_num, qiov,
	368	nb_sectors, cb, opaque);
	369
	370	acb->verify = blkverify_verify_readv;
	371	acb->buf = qemu_blockalign(bs->file, qiov->size);
	372	qemu_iovec_init(&acb->raw_qiov, acb->qiov->niov);
	373	blkverify_iovec_clone(&acb->raw_qiov, qiov, acb->buf);
	374
ad54ae80 PB	375	bdrv_aio_readv(s->test_file, sector_num, qiov, nb_sectors,
	376	blkverify_aio_cb, acb);
	377	bdrv_aio_readv(bs->file, sector_num, &acb->raw_qiov, nb_sectors,
	378	blkverify_aio_cb, acb);
d9d33417 SH	379	return &acb->common;
	380	}
	381
	382	static BlockDriverAIOCB blkverify_aio_writev(BlockDriverState bs,
	383	int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
	384	BlockDriverCompletionFunc cb, void opaque)
	385	{
	386	BDRVBlkverifyState *s = bs->opaque;
	387	BlkverifyAIOCB *acb = blkverify_aio_get(bs, true, sector_num, qiov,
	388	nb_sectors, cb, opaque);
	389
ad54ae80 PB	390	bdrv_aio_writev(s->test_file, sector_num, qiov, nb_sectors,
	391	blkverify_aio_cb, acb);
	392	bdrv_aio_writev(bs->file, sector_num, qiov, nb_sectors,
	393	blkverify_aio_cb, acb);
d9d33417 SH	394	return &acb->common;
	395	}
	396
	397	static BlockDriverAIOCB blkverify_aio_flush(BlockDriverState bs,
	398	BlockDriverCompletionFunc *cb,
	399	void *opaque)
	400	{
	401	BDRVBlkverifyState *s = bs->opaque;
	402
	403	/* Only flush test file, the raw file is not important */
	404	return bdrv_aio_flush(s->test_file, cb, opaque);
	405	}
	406
	407	static BlockDriver bdrv_blkverify = {
16c79092 KW	408	.format_name = "blkverify",
	409	.protocol_name = "blkverify",
	410	.instance_size = sizeof(BDRVBlkverifyState),
	411
	412	.bdrv_parse_filename = blkverify_parse_filename,
	413	.bdrv_file_open = blkverify_open,
	414	.bdrv_close = blkverify_close,
	415	.bdrv_getlength = blkverify_getlength,
	416
	417	.bdrv_aio_readv = blkverify_aio_readv,
	418	.bdrv_aio_writev = blkverify_aio_writev,
	419	.bdrv_aio_flush = blkverify_aio_flush,
d9d33417 SH	420	};
	421
	422	static void bdrv_blkverify_init(void)
	423	{
	424	bdrv_register(&bdrv_blkverify);
	425	}
	426
	427	block_init(bdrv_blkverify_init);