qemu/block/blkverify.c
Vladimir Sementsov-Ogievskiy e75abedab7 block: use int64_t instead of uint64_t in driver write handlers
We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

So, convert driver write handlers parameters which are already 64bit to
signed type.

While being here, convert also flags parameter to be BdrvRequestFlags.

Now let's consider all callers. Simple

  git grep '\->bdrv_\(aio\|co\)_pwritev\(_part\)\?'

shows that's there three callers of driver function:

 bdrv_driver_pwritev() and bdrv_driver_pwritev_compressed() in
 block/io.c, both pass int64_t, checked by bdrv_check_qiov_request() to
 be non-negative.

 qcow2_save_vmstate() does bdrv_check_qiov_request().

Still, the functions may be called directly, not only by drv->...
Let's check:

git grep '\.bdrv_\(aio\|co\)_pwritev\(_part\)\?\s*=' | \
awk '{print $4}' | sed 's/,//' | sed 's/&//' | sort | uniq | \
while read func; do git grep "$func(" | \
grep -v "$func(BlockDriverState"; done

shows several callers:

qcow2:
  qcow2_co_truncate() write at most up to @offset, which is checked in
    generic qcow2_co_truncate() by bdrv_check_request().
  qcow2_co_pwritev_compressed_task() pass the request (or part of the
    request) that already went through normal write path, so it should
    be OK

qcow:
  qcow_co_pwritev_compressed() pass int64_t, it's updated by this patch

quorum:
  quorum_co_pwrite_zeroes() pass int64_t and int - OK

throttle:
  throttle_co_pwritev_compressed() pass int64_t, it's updated by this
  patch

vmdk:
  vmdk_co_pwritev_compressed() pass int64_t, it's updated by this
  patch

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210903102807.27127-5-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-09-29 13:46:31 -05:00

336 lines
9.9 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 "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu/sockets.h" /* for EINPROGRESS on Windows */
#include "block/block_int.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qstring.h"
#include "qemu/cutils.h"
#include "qemu/module.h"
#include "qemu/option.h"
typedef struct {
BdrvChild *test_file;
} BDRVBlkverifyState;
typedef struct BlkverifyRequest {
Coroutine *co;
BlockDriverState *bs;
/* Request metadata */
bool is_write;
uint64_t offset;
uint64_t bytes;
int flags;
int (*request_fn)(BdrvChild *, int64_t, int64_t, QEMUIOVector *,
BdrvRequestFlags);
int ret; /* test image result */
int raw_ret; /* raw image result */
unsigned int done; /* completion counter */
QEMUIOVector *qiov; /* user I/O vector */
QEMUIOVector *raw_qiov; /* cloned I/O vector for raw file */
} BlkverifyRequest;
static void GCC_FMT_ATTR(2, 3) blkverify_err(BlkverifyRequest *r,
const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
fprintf(stderr, "blkverify: %s offset=%" PRId64 " bytes=%" PRId64 " ",
r->is_write ? "write" : "read", r->offset, r->bytes);
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_str(options, "x-image", 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);
qdict_put(options, "x-raw", raw_path);
/* TODO Allow multi-level nesting and set file.filename here */
filename = c + 1;
qdict_put_str(options, "x-image", 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;
int ret;
opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
if (!qemu_opts_absorb_qdict(opts, options, errp)) {
ret = -EINVAL;
goto fail;
}
/* Open the raw file */
bs->file = bdrv_open_child(qemu_opt_get(opts, "x-raw"), options, "raw",
bs, &child_of_bds,
BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY,
false, errp);
if (!bs->file) {
ret = -EINVAL;
goto fail;
}
/* Open the test file */
s->test_file = bdrv_open_child(qemu_opt_get(opts, "x-image"), options,
"test", bs, &child_of_bds, BDRV_CHILD_DATA,
false, errp);
if (!s->test_file) {
ret = -EINVAL;
goto fail;
}
bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED;
bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED;
ret = 0;
fail:
qemu_opts_del(opts);
return ret;
}
static void blkverify_close(BlockDriverState *bs)
{
BDRVBlkverifyState *s = bs->opaque;
bdrv_unref_child(bs, s->test_file);
s->test_file = NULL;
}
static int64_t blkverify_getlength(BlockDriverState *bs)
{
BDRVBlkverifyState *s = bs->opaque;
return bdrv_getlength(s->test_file->bs);
}
static void coroutine_fn blkverify_do_test_req(void *opaque)
{
BlkverifyRequest *r = opaque;
BDRVBlkverifyState *s = r->bs->opaque;
r->ret = r->request_fn(s->test_file, r->offset, r->bytes, r->qiov,
r->flags);
r->done++;
qemu_coroutine_enter_if_inactive(r->co);
}
static void coroutine_fn blkverify_do_raw_req(void *opaque)
{
BlkverifyRequest *r = opaque;
r->raw_ret = r->request_fn(r->bs->file, r->offset, r->bytes, r->raw_qiov,
r->flags);
r->done++;
qemu_coroutine_enter_if_inactive(r->co);
}
static int coroutine_fn
blkverify_co_prwv(BlockDriverState *bs, BlkverifyRequest *r, uint64_t offset,
uint64_t bytes, QEMUIOVector *qiov, QEMUIOVector *raw_qiov,
int flags, bool is_write)
{
Coroutine *co_a, *co_b;
*r = (BlkverifyRequest) {
.co = qemu_coroutine_self(),
.bs = bs,
.offset = offset,
.bytes = bytes,
.qiov = qiov,
.raw_qiov = raw_qiov,
.flags = flags,
.is_write = is_write,
.request_fn = is_write ? bdrv_co_pwritev : bdrv_co_preadv,
};
co_a = qemu_coroutine_create(blkverify_do_test_req, r);
co_b = qemu_coroutine_create(blkverify_do_raw_req, r);
qemu_coroutine_enter(co_a);
qemu_coroutine_enter(co_b);
while (r->done < 2) {
qemu_coroutine_yield();
}
if (r->ret != r->raw_ret) {
blkverify_err(r, "return value mismatch %d != %d", r->ret, r->raw_ret);
}
return r->ret;
}
static int coroutine_fn
blkverify_co_preadv(BlockDriverState *bs, int64_t offset, int64_t bytes,
QEMUIOVector *qiov, BdrvRequestFlags flags)
{
BlkverifyRequest r;
QEMUIOVector raw_qiov;
void *buf;
ssize_t cmp_offset;
int ret;
buf = qemu_blockalign(bs->file->bs, qiov->size);
qemu_iovec_init(&raw_qiov, qiov->niov);
qemu_iovec_clone(&raw_qiov, qiov, buf);
ret = blkverify_co_prwv(bs, &r, offset, bytes, qiov, &raw_qiov, flags,
false);
cmp_offset = qemu_iovec_compare(qiov, &raw_qiov);
if (cmp_offset != -1) {
blkverify_err(&r, "contents mismatch at offset %" PRId64,
offset + cmp_offset);
}
qemu_iovec_destroy(&raw_qiov);
qemu_vfree(buf);
return ret;
}
static int coroutine_fn
blkverify_co_pwritev(BlockDriverState *bs, int64_t offset, int64_t bytes,
QEMUIOVector *qiov, BdrvRequestFlags flags)
{
BlkverifyRequest r;
return blkverify_co_prwv(bs, &r, offset, bytes, qiov, qiov, flags, true);
}
static int blkverify_co_flush(BlockDriverState *bs)
{
BDRVBlkverifyState *s = bs->opaque;
/* Only flush test file, the raw file is not important */
return bdrv_co_flush(s->test_file->bs);
}
static bool blkverify_recurse_can_replace(BlockDriverState *bs,
BlockDriverState *to_replace)
{
BDRVBlkverifyState *s = bs->opaque;
/*
* blkverify quits the whole qemu process if there is a mismatch
* between bs->file->bs and s->test_file->bs. Therefore, we know
* know that both must match bs and we can recurse down to either.
*/
return bdrv_recurse_can_replace(bs->file->bs, to_replace) ||
bdrv_recurse_can_replace(s->test_file->bs, to_replace);
}
static void blkverify_refresh_filename(BlockDriverState *bs)
{
BDRVBlkverifyState *s = bs->opaque;
if (bs->file->bs->exact_filename[0]
&& s->test_file->bs->exact_filename[0])
{
int ret = snprintf(bs->exact_filename, sizeof(bs->exact_filename),
"blkverify:%s:%s",
bs->file->bs->exact_filename,
s->test_file->bs->exact_filename);
if (ret >= sizeof(bs->exact_filename)) {
/* An overflow makes the filename unusable, so do not report any */
bs->exact_filename[0] = 0;
}
}
}
static char *blkverify_dirname(BlockDriverState *bs, Error **errp)
{
/* In general, there are two BDSs with different dirnames below this one;
* so there is no unique dirname we could return (unless both are equal by
* chance). Therefore, to be consistent, just always return NULL. */
error_setg(errp, "Cannot generate a base directory for blkverify nodes");
return NULL;
}
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_child_perm = bdrv_default_perms,
.bdrv_getlength = blkverify_getlength,
.bdrv_refresh_filename = blkverify_refresh_filename,
.bdrv_dirname = blkverify_dirname,
.bdrv_co_preadv = blkverify_co_preadv,
.bdrv_co_pwritev = blkverify_co_pwritev,
.bdrv_co_flush = blkverify_co_flush,
.is_filter = true,
.bdrv_recurse_can_replace = blkverify_recurse_can_replace,
};
static void bdrv_blkverify_init(void)
{
bdrv_register(&bdrv_blkverify);
}
block_init(bdrv_blkverify_init);