qemu/block/blkverify.c
Benoît Canet b5042a3622 block: Rewrite the snapshot authorization mechanism for block filters.
This patch keep the recursive way of doing things but simplify it by giving
two responsabilities to all block filters implementors.

They will need to do two things:

-Set the is_filter field of their block driver to true.

-Implement the bdrv_recurse_is_first_non_filter method of their block driver like
it is done on the Quorum block driver. (block/quorum.c)

[Paolo Bonzini <pbonzini@redhat.com> pointed out that this patch changes
the semantics of blkverify, which now recurses down both bs->file and
s->test_file.
-- Stefan]

Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-03-13 14:23:27 +01:00

329 lines
9.5 KiB
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)) {
/* There was no prefix; therefore, all options have to be already
present in the QDict (except for the filename) */
qdict_put(options, "x-image", qstring_from_str(filename));
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;
int ret;
opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
qemu_opts_absorb_qdict(opts, options, &local_err);
if (local_err) {
error_propagate(errp, local_err);
ret = -EINVAL;
goto fail;
}
/* Open the raw file */
assert(bs->file == NULL);
ret = bdrv_open_image(&bs->file, qemu_opt_get(opts, "x-raw"), options,
"raw", flags | BDRV_O_PROTOCOL, false, &local_err);
if (ret < 0) {
error_propagate(errp, local_err);
goto fail;
}
/* Open the test file */
assert(s->test_file == NULL);
ret = bdrv_open_image(&s->test_file, qemu_opt_get(opts, "x-image"), options,
"test", flags, false, &local_err);
if (ret < 0) {
error_propagate(errp, local_err);
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);
}
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 = qemu_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);
qemu_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 bool blkverify_recurse_is_first_non_filter(BlockDriverState *bs,
BlockDriverState *candidate)
{
BDRVBlkverifyState *s = bs->opaque;
bool perm = bdrv_recurse_is_first_non_filter(bs->file, candidate);
if (perm) {
return true;
}
return bdrv_recurse_is_first_non_filter(s->test_file, candidate);
}
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,
.is_filter = true,
.bdrv_recurse_is_first_non_filter = blkverify_recurse_is_first_non_filter,
};
static void bdrv_blkverify_init(void)
{
bdrv_register(&bdrv_blkverify);
}
block_init(bdrv_blkverify_init);