From: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
To: qemu-block@nongnu.org
Cc: kwolf@redhat.com, vsementsov@virtuozzo.com, armbru@redhat.com,
qemu-devel@nongnu.org, andrey.shinkevich@virtuozzo.com,
den@openvz.org, mreitz@redhat.com
Subject: [PATCH 2/2] qcow2: dump QCOW2 metadata
Date: Fri, 27 Dec 2019 14:43:59 +0300 [thread overview]
Message-ID: <1577447039-400109-3-git-send-email-andrey.shinkevich@virtuozzo.com> (raw)
In-Reply-To: <1577447039-400109-1-git-send-email-andrey.shinkevich@virtuozzo.com>
Let QEMU-IMG CHECK command show QCOW2 structure to inform a user about
metadata allocations on disk. Introduce '-M'('--dump-meta') key option.
Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
---
block/qcow2-bitmap.c | 53 ++++++++++++++++++++++++++++---
block/qcow2-refcount.c | 84 +++++++++++++++++++++++++++++++++++++++++---------
block/qcow2.c | 30 ++++++++++++++++++
block/qcow2.h | 6 ++--
include/block/block.h | 3 +-
qemu-img.c | 29 ++++++++++++++++-
qemu-img.texi | 2 +-
7 files changed, 183 insertions(+), 24 deletions(-)
diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c
index c6c8ebb..4f7b375 100644
--- a/block/qcow2-bitmap.c
+++ b/block/qcow2-bitmap.c
@@ -659,20 +659,29 @@ fail:
int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
void **refcount_table,
- int64_t *refcount_table_size)
+ int64_t *refcount_table_size,
+ Qcow2Bitmaps *bitmaps)
{
int ret;
BDRVQcow2State *s = bs->opaque;
Qcow2BitmapList *bm_list;
Qcow2Bitmap *bm;
+ Qcow2BitmapDirectoryEntryList **pp_dir =
+ bitmaps ? &bitmaps->bitmap_dir->dir_entries : NULL;
if (s->nb_bitmaps == 0) {
return 0;
}
+ if (bitmaps) {
+ bitmaps->nb_bitmaps = s->nb_bitmaps;
+ }
+
ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table, refcount_table_size,
s->bitmap_directory_offset,
- s->bitmap_directory_size);
+ s->bitmap_directory_size,
+ bitmaps ? bitmaps->bitmap_dir->location
+ : NULL);
if (ret < 0) {
return ret;
}
@@ -686,12 +695,28 @@ int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
QSIMPLEQ_FOREACH(bm, bm_list, entry) {
uint64_t *bitmap_table = NULL;
+ Qcow2BitmapTblEntryList **pp_table;
int i;
+ Qcow2BitmapDirectoryEntry *bmde = NULL;
+ if (bitmaps) {
+ bmde = g_new0(Qcow2BitmapDirectoryEntry, 1);
+ bmde->bitmap_name = g_strdup(bm->name);
+ bmde->bitmap_table = g_new0(Qcow2BitmapTbl, 1);
+ bmde->bitmap_table->location = g_new0(Qcow2Allocation, 1);
+ Qcow2BitmapDirectoryEntryList *obj =
+ g_new0(Qcow2BitmapDirectoryEntryList, 1);
+ obj->value = bmde;
+ *pp_dir = obj;
+ pp_dir = &obj->next;
+ }
+
ret = qcow2_inc_refcounts_imrt(bs, res,
refcount_table, refcount_table_size,
bm->table.offset,
- bm->table.size * sizeof(uint64_t));
+ bm->table.size * sizeof(uint64_t),
+ bmde ? bmde->bitmap_table->location
+ : NULL);
if (ret < 0) {
goto out;
}
@@ -702,6 +727,8 @@ int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
goto out;
}
+ pp_table = bmde ? &bmde->bitmap_table->table_entries : NULL;
+
for (i = 0; i < bm->table.size; ++i) {
uint64_t entry = bitmap_table[i];
uint64_t offset = entry & BME_TABLE_ENTRY_OFFSET_MASK;
@@ -711,13 +738,31 @@ int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
continue;
}
+ Qcow2BitmapTblEntry *bmte = NULL;
+ if (bmde) {
+ bmte = g_new0(Qcow2BitmapTblEntry, 1);
+ bmte->type = offset ? QCOW2_BITMAP_TBL_ENTRY_TYPE_SERIALIZED :
+ entry & BME_TABLE_ENTRY_FLAG_ALL_ONES;
+ if (offset) {
+ bmte->cluster = g_new0(Qcow2Allocation, 1);
+ }
+ bmte->has_cluster = !!(bmte->cluster);
+ Qcow2BitmapTblEntryList *elem =
+ g_new0(Qcow2BitmapTblEntryList, 1);
+ elem->value = bmte;
+ *pp_table = elem;
+ pp_table = &elem->next;
+ }
+
if (offset == 0) {
continue;
}
ret = qcow2_inc_refcounts_imrt(bs, res,
refcount_table, refcount_table_size,
- offset, s->cluster_size);
+ offset, s->cluster_size,
+ bmte && bmte->cluster ? bmte->cluster
+ : NULL);
if (ret < 0) {
g_free(bitmap_table);
goto out;
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index f67ac6b..ac1ae42 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -1521,7 +1521,8 @@ static int realloc_refcount_array(BDRVQcow2State *s, void **array,
int qcow2_inc_refcounts_imrt(BlockDriverState *bs, BdrvCheckResult *res,
void **refcount_table,
int64_t *refcount_table_size,
- int64_t offset, int64_t size)
+ int64_t offset, int64_t size,
+ Qcow2Allocation *qcow2_alloc)
{
BDRVQcow2State *s = bs->opaque;
uint64_t start, last, cluster_offset, k, refcount;
@@ -1550,6 +1551,11 @@ int qcow2_inc_refcounts_imrt(BlockDriverState *bs, BdrvCheckResult *res,
return 0;
}
+ if (qcow2_alloc) {
+ qcow2_alloc->offset = offset;
+ qcow2_alloc->size = size;
+ }
+
start = start_of_cluster(s, offset);
last = start_of_cluster(s, offset + size - 1);
for(cluster_offset = start; cluster_offset <= last;
@@ -1643,7 +1649,7 @@ static int check_refcounts_l2(BlockDriverState *bs, BdrvCheckResult *res,
ret = qcow2_inc_refcounts_imrt(
bs, res, refcount_table, refcount_table_size,
l2_entry & QCOW2_COMPRESSED_SECTOR_MASK,
- nb_csectors * QCOW2_COMPRESSED_SECTOR_SIZE);
+ nb_csectors * QCOW2_COMPRESSED_SECTOR_SIZE, NULL);
if (ret < 0) {
goto fail;
}
@@ -1731,7 +1737,7 @@ static int check_refcounts_l2(BlockDriverState *bs, BdrvCheckResult *res,
if (!has_data_file(bs)) {
ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table,
refcount_table_size,
- offset, s->cluster_size);
+ offset, s->cluster_size, NULL);
if (ret < 0) {
goto fail;
}
@@ -1769,17 +1775,20 @@ static int check_refcounts_l1(BlockDriverState *bs,
void **refcount_table,
int64_t *refcount_table_size,
int64_t l1_table_offset, int l1_size,
- int flags, BdrvCheckMode fix, bool active)
+ int flags, BdrvCheckMode fix, bool active,
+ Qcow2L1Table *l1t)
{
BDRVQcow2State *s = bs->opaque;
uint64_t *l1_table = NULL, l2_offset, l1_size2;
+ Qcow2AllocationList **plist = l1t ? &l1t->l2_list : NULL;
int i, ret;
l1_size2 = l1_size * sizeof(uint64_t);
/* Mark L1 table as used */
ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table, refcount_table_size,
- l1_table_offset, l1_size2);
+ l1_table_offset, l1_size2,
+ l1t ? l1t->location : NULL);
if (ret < 0) {
goto fail;
}
@@ -1808,9 +1817,19 @@ static int check_refcounts_l1(BlockDriverState *bs,
if (l2_offset) {
/* Mark L2 table as used */
l2_offset &= L1E_OFFSET_MASK;
+
+ Qcow2Allocation *l2t = NULL;
+ if (l1t) {
+ l2t = g_new0(Qcow2Allocation, 1);
+ Qcow2AllocationList *obj = g_new0(Qcow2AllocationList, 1);
+ obj->value = l2t;
+ *plist = obj;
+ plist = &obj->next;
+ }
+
ret = qcow2_inc_refcounts_imrt(bs, res,
refcount_table, refcount_table_size,
- l2_offset, s->cluster_size);
+ l2_offset, s->cluster_size, l2t);
if (ret < 0) {
goto fail;
}
@@ -2047,7 +2066,7 @@ static int check_refblocks(BlockDriverState *bs, BdrvCheckResult *res,
res->corruptions_fixed++;
ret = qcow2_inc_refcounts_imrt(bs, res,
refcount_table, nb_clusters,
- offset, s->cluster_size);
+ offset, s->cluster_size, NULL);
if (ret < 0) {
return ret;
}
@@ -2066,7 +2085,7 @@ resize_fail:
if (offset != 0) {
ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table, nb_clusters,
- offset, s->cluster_size);
+ offset, s->cluster_size, NULL);
if (ret < 0) {
return ret;
}
@@ -2093,6 +2112,9 @@ static int calculate_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
BDRVQcow2State *s = bs->opaque;
int64_t i;
QCowSnapshot *sn;
+ bool has_snapshots = res->viscera && res->viscera->snapshot_table;
+ Qcow2L1TableList **plist = has_snapshots ?
+ &res->viscera->snapshot_table->l1_list : NULL;
int ret;
if (!*refcount_table) {
@@ -2106,16 +2128,25 @@ static int calculate_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
}
/* header */
+ if (res->viscera) {
+ res->viscera->qcow2_header->version = s->qcow_version;
+ }
ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table, nb_clusters,
- 0, s->cluster_size);
+ 0, s->cluster_size,
+ res->viscera ?
+ res->viscera->qcow2_header->location : NULL);
if (ret < 0) {
return ret;
}
/* current L1 table */
+ if (res->viscera) {
+ res->viscera->active_l1->name = g_strdup("L1 active table");
+ }
ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters,
s->l1_table_offset, s->l1_size, CHECK_FRAG_INFO,
- fix, true);
+ fix, true,
+ res->viscera ? res->viscera->active_l1 : NULL);
if (ret < 0) {
return ret;
}
@@ -2143,15 +2174,30 @@ static int calculate_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
res->corruptions++;
continue;
}
+
+ Qcow2L1Table *l1t = NULL;
+ if (has_snapshots) {
+ l1t = g_new0(Qcow2L1Table, 1);
+ l1t->location = g_new0(Qcow2Allocation, 1);
+ l1t->name = g_strdup(sn->name);
+ Qcow2L1TableList *obj = g_new0(Qcow2L1TableList, 1);
+ obj->value = l1t;
+ *plist = obj;
+ plist = &obj->next;
+ }
+
ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters,
sn->l1_table_offset, sn->l1_size, 0, fix,
- false);
+ false, l1t);
if (ret < 0) {
return ret;
}
}
ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table, nb_clusters,
- s->snapshots_offset, s->snapshots_size);
+ s->snapshots_offset, s->snapshots_size,
+ has_snapshots ?
+ res->viscera->snapshot_table->location
+ : NULL);
if (ret < 0) {
return ret;
}
@@ -2159,7 +2205,10 @@ static int calculate_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
/* refcount data */
ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table, nb_clusters,
s->refcount_table_offset,
- s->refcount_table_size * sizeof(uint64_t));
+ s->refcount_table_size * sizeof(uint64_t),
+ res->viscera ?
+ res->viscera->refcount_table->location
+ : NULL);
if (ret < 0) {
return ret;
}
@@ -2168,14 +2217,19 @@ static int calculate_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
if (s->crypto_header.length) {
ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table, nb_clusters,
s->crypto_header.offset,
- s->crypto_header.length);
+ s->crypto_header.length,
+ res->viscera ?
+ res->viscera->crypt_header->location
+ : NULL);
if (ret < 0) {
return ret;
}
}
/* bitmaps */
- ret = qcow2_check_bitmaps_refcounts(bs, res, refcount_table, nb_clusters);
+ ret = qcow2_check_bitmaps_refcounts(bs, res, refcount_table, nb_clusters,
+ res->viscera ? res->viscera->bitmaps
+ : NULL);
if (ret < 0) {
return ret;
}
diff --git a/block/qcow2.c b/block/qcow2.c
index 7c18721..39cf918 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -590,6 +590,7 @@ static int coroutine_fn qcow2_co_check_locked(BlockDriverState *bs,
BdrvCheckResult *result,
BdrvCheckMode fix)
{
+ BDRVQcow2State *s = bs->opaque;
BdrvCheckResult snapshot_res = {};
BdrvCheckResult refcount_res = {};
int ret;
@@ -602,6 +603,35 @@ static int coroutine_fn qcow2_co_check_locked(BlockDriverState *bs,
return ret;
}
+ if (fix & BDRV_DUMP_META) {
+ result->viscera = g_new0(Qcow2Metadata, 1);
+ result->viscera->qcow2_header = g_new0(Qcow2Header, 1);
+ result->viscera->qcow2_header->location = g_new0(Qcow2Allocation, 1);
+ result->viscera->active_l1 = g_new0(Qcow2L1Table, 1);
+ result->viscera->active_l1->location = g_new0(Qcow2Allocation, 1);
+ result->viscera->refcount_table = g_new0(Qcow2RefcountTable, 1);
+ result->viscera->refcount_table->location = g_new0(Qcow2Allocation, 1);
+
+ refcount_res.viscera = result->viscera;
+
+ if (s->crypto_header.length) {
+ result->viscera->crypt_header = g_new0(Qcow2EncryptionHeader, 1);
+ result->viscera->crypt_header->location =
+ g_new0(Qcow2Allocation, 1);
+ }
+ if (s->nb_bitmaps) {
+ result->viscera->bitmaps = g_new0(Qcow2Bitmaps, 1);
+ result->viscera->bitmaps->bitmap_dir = g_new0(Qcow2BitmapDir, 1);
+ result->viscera->bitmaps->bitmap_dir->location =
+ g_new0(Qcow2Allocation, 1);
+ }
+ if (s->nb_snapshots) {
+ result->viscera->snapshot_table = g_new0(Qcow2SnapshotsTable, 1);
+ result->viscera->snapshot_table->location =
+ g_new0(Qcow2Allocation, 1);
+ }
+ }
+
ret = qcow2_check_refcounts(bs, &refcount_res, fix);
qcow2_add_check_result(result, &refcount_res, true);
if (ret < 0) {
diff --git a/block/qcow2.h b/block/qcow2.h
index 0942126..8d615e2 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -662,7 +662,8 @@ int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset,
int qcow2_inc_refcounts_imrt(BlockDriverState *bs, BdrvCheckResult *res,
void **refcount_table,
int64_t *refcount_table_size,
- int64_t offset, int64_t size);
+ int64_t offset, int64_t size,
+ Qcow2Allocation *qcow2_alloc);
int qcow2_change_refcount_order(BlockDriverState *bs, int refcount_order,
BlockDriverAmendStatusCB *status_cb,
@@ -751,7 +752,8 @@ void qcow2_cache_discard(Qcow2Cache *c, void *table);
/* qcow2-bitmap.c functions */
int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
void **refcount_table,
- int64_t *refcount_table_size);
+ int64_t *refcount_table_size,
+ Qcow2Bitmaps *bitmaps);
bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp);
Qcow2BitmapInfoList *qcow2_get_bitmap_info_list(BlockDriverState *bs,
Error **errp);
diff --git a/include/block/block.h b/include/block/block.h
index 1df9848..b1fc275 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -373,7 +373,6 @@ int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base,
Error **errp);
void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base);
-
typedef struct BdrvCheckResult {
int corruptions;
int leaks;
@@ -382,11 +381,13 @@ typedef struct BdrvCheckResult {
int leaks_fixed;
int64_t image_end_offset;
BlockFragInfo bfi;
+ Qcow2Metadata *viscera;
} BdrvCheckResult;
typedef enum {
BDRV_FIX_LEAKS = 1,
BDRV_FIX_ERRORS = 2,
+ BDRV_DUMP_META = 4,
} BdrvCheckMode;
int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix);
diff --git a/qemu-img.c b/qemu-img.c
index 95a24b9..840eee2 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -173,6 +173,7 @@ static void QEMU_NORETURN help(void)
" '-r leaks' repairs only cluster leaks, whereas '-r all' fixes all\n"
" kinds of errors, with a higher risk of choosing the wrong fix or\n"
" hiding corruption that has already occurred.\n"
+ " '-M' Dump QCOW2 metadata to stdout in JSON format.\n"
"\n"
"Parameters to convert subcommand:\n"
" '-m' specifies how many coroutines work in parallel during the convert\n"
@@ -659,6 +660,14 @@ static int collect_image_check(BlockDriverState *bs,
check->has_fragmented_clusters = result.bfi.fragmented_clusters != 0;
check->compressed_clusters = result.bfi.compressed_clusters;
check->has_compressed_clusters = result.bfi.compressed_clusters != 0;
+ check->viscera = result.viscera;
+ check->has_viscera = !!(result.viscera);
+
+ if (check->has_viscera) {
+ check->viscera->has_crypt_header = !!(check->viscera->crypt_header);
+ check->viscera->has_bitmaps = !!(check->viscera->bitmaps);
+ check->viscera->has_snapshot_table = !!(check->viscera->snapshot_table);
+ }
return 0;
}
@@ -701,9 +710,10 @@ static int img_check(int argc, char **argv)
{"object", required_argument, 0, OPTION_OBJECT},
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
{"force-share", no_argument, 0, 'U'},
+ {"dump-meta", no_argument, 0, 'M'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, ":hf:r:T:qU",
+ c = getopt_long(argc, argv, ":hf:r:T:qU:M",
long_options, &option_index);
if (c == -1) {
break;
@@ -745,6 +755,9 @@ static int img_check(int argc, char **argv)
case 'U':
force_share = true;
break;
+ case 'M':
+ fix |= BDRV_DUMP_META;
+ break;
case OPTION_OBJECT: {
QemuOpts *opts;
opts = qemu_opts_parse_noisily(&qemu_object_opts,
@@ -772,6 +785,11 @@ static int img_check(int argc, char **argv)
return 1;
}
+ if ((fix & BDRV_DUMP_META) && output_format != OFORMAT_JSON) {
+ error_report("Metadata output in JSON format only");
+ return 1;
+ }
+
if (qemu_opts_foreach(&qemu_object_opts,
user_creatable_add_opts_foreach,
qemu_img_object_print_help, &error_fatal)) {
@@ -792,6 +810,15 @@ static int img_check(int argc, char **argv)
bs = blk_bs(blk);
check = g_new0(ImageCheck, 1);
+
+ if (fix & BDRV_DUMP_META) {
+ if (strcmp(bs->drv->format_name, "qcow2")) {
+ error_report("Metadata output supported for QCOW2 format only");
+ ret = -ENOTSUP;
+ goto fail;
+ }
+ }
+
ret = collect_image_check(bs, check, filename, fmt, fix);
if (ret == -ENOTSUP) {
diff --git a/qemu-img.texi b/qemu-img.texi
index b5156d6..873e80a 100644
--- a/qemu-img.texi
+++ b/qemu-img.texi
@@ -230,7 +230,7 @@ specified as well.
For write tests, by default a buffer filled with zeros is written. This can be
overridden with a pattern byte specified by @var{pattern}.
-@item check [--object @var{objectdef}] [--image-opts] [-q] [-f @var{fmt}] [--output=@var{ofmt}] [-r [leaks | all]] [-T @var{src_cache}] [-U] @var{filename}
+@item check [--object @var{objectdef}] [--image-opts] [-M] [-q] [-f @var{fmt}] [--output=@var{ofmt}] [-r [leaks | all]] [-T @var{src_cache}] [-U] @var{filename}
Perform a consistency check on the disk image @var{filename}. The command can
output in the format @var{ofmt} which is either @code{human} or @code{json}.
--
1.8.3.1
next prev parent reply other threads:[~2019-12-27 11:46 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-27 11:43 [PATCH 0/2] Dump QCOW2 metadata Andrey Shinkevich
2019-12-27 11:43 ` [PATCH 1/2] qcow2: introduce Qcow2Metadata structure Andrey Shinkevich
2020-01-07 22:07 ` Eric Blake
2020-01-13 9:49 ` Andrey Shinkevich
2019-12-27 11:43 ` Andrey Shinkevich [this message]
2020-01-07 22:11 ` [PATCH 2/2] qcow2: dump QCOW2 metadata Eric Blake
2020-01-13 10:30 ` Andrey Shinkevich
2020-01-13 16:16 ` Eric Blake
2020-01-13 17:02 ` Andrey Shinkevich
2020-01-13 17:27 ` Eric Blake
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