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-rw-r--r--block/Makefile.objs2
-rw-r--r--block/qcow2-bitmap.c439
-rw-r--r--block/qcow2-refcount.c6
-rw-r--r--block/qcow2.c125
-rw-r--r--block/qcow2.h27
5 files changed, 593 insertions, 6 deletions
diff --git a/block/Makefile.objs b/block/Makefile.objs
index f9368b52b8..2aaede4ae1 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -1,5 +1,5 @@
block-obj-y += raw-format.o qcow.o vdi.o vmdk.o cloop.o bochs.o vpc.o vvfat.o dmg.o
-block-obj-y += qcow2.o qcow2-refcount.o qcow2-cluster.o qcow2-snapshot.o qcow2-cache.o
+block-obj-y += qcow2.o qcow2-refcount.o qcow2-cluster.o qcow2-snapshot.o qcow2-cache.o qcow2-bitmap.o
block-obj-y += qed.o qed-l2-cache.o qed-table.o qed-cluster.o
block-obj-y += qed-check.o
block-obj-y += vhdx.o vhdx-endian.o vhdx-log.o
diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c
new file mode 100644
index 0000000000..b8e472b3e8
--- /dev/null
+++ b/block/qcow2-bitmap.c
@@ -0,0 +1,439 @@
+/*
+ * Bitmaps for the QCOW version 2 format
+ *
+ * Copyright (c) 2014-2017 Vladimir Sementsov-Ogievskiy
+ *
+ * This file is derived from qcow2-snapshot.c, original copyright:
+ * Copyright (c) 2004-2006 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+
+#include "block/block_int.h"
+#include "block/qcow2.h"
+
+/* NOTICE: BME here means Bitmaps Extension and used as a namespace for
+ * _internal_ constants. Please do not use this _internal_ abbreviation for
+ * other needs and/or outside of this file. */
+
+/* Bitmap directory entry constraints */
+#define BME_MAX_TABLE_SIZE 0x8000000
+#define BME_MAX_PHYS_SIZE 0x20000000 /* restrict BdrvDirtyBitmap size in RAM */
+#define BME_MAX_GRANULARITY_BITS 31
+#define BME_MIN_GRANULARITY_BITS 9
+#define BME_MAX_NAME_SIZE 1023
+
+/* Bitmap directory entry flags */
+#define BME_RESERVED_FLAGS 0xfffffffcU
+
+/* bits [1, 8] U [56, 63] are reserved */
+#define BME_TABLE_ENTRY_RESERVED_MASK 0xff000000000001feULL
+#define BME_TABLE_ENTRY_OFFSET_MASK 0x00fffffffffffe00ULL
+#define BME_TABLE_ENTRY_FLAG_ALL_ONES (1ULL << 0)
+
+typedef struct QEMU_PACKED Qcow2BitmapDirEntry {
+ /* header is 8 byte aligned */
+ uint64_t bitmap_table_offset;
+
+ uint32_t bitmap_table_size;
+ uint32_t flags;
+
+ uint8_t type;
+ uint8_t granularity_bits;
+ uint16_t name_size;
+ uint32_t extra_data_size;
+ /* extra data follows */
+ /* name follows */
+} Qcow2BitmapDirEntry;
+
+typedef struct Qcow2BitmapTable {
+ uint64_t offset;
+ uint32_t size; /* number of 64bit entries */
+ QSIMPLEQ_ENTRY(Qcow2BitmapTable) entry;
+} Qcow2BitmapTable;
+
+typedef struct Qcow2Bitmap {
+ Qcow2BitmapTable table;
+ uint32_t flags;
+ uint8_t granularity_bits;
+ char *name;
+
+ QSIMPLEQ_ENTRY(Qcow2Bitmap) entry;
+} Qcow2Bitmap;
+typedef QSIMPLEQ_HEAD(Qcow2BitmapList, Qcow2Bitmap) Qcow2BitmapList;
+
+typedef enum BitmapType {
+ BT_DIRTY_TRACKING_BITMAP = 1
+} BitmapType;
+
+static int check_table_entry(uint64_t entry, int cluster_size)
+{
+ uint64_t offset;
+
+ if (entry & BME_TABLE_ENTRY_RESERVED_MASK) {
+ return -EINVAL;
+ }
+
+ offset = entry & BME_TABLE_ENTRY_OFFSET_MASK;
+ if (offset != 0) {
+ /* if offset specified, bit 0 is reserved */
+ if (entry & BME_TABLE_ENTRY_FLAG_ALL_ONES) {
+ return -EINVAL;
+ }
+
+ if (offset % cluster_size != 0) {
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+static int bitmap_table_load(BlockDriverState *bs, Qcow2BitmapTable *tb,
+ uint64_t **bitmap_table)
+{
+ int ret;
+ BDRVQcow2State *s = bs->opaque;
+ uint32_t i;
+ uint64_t *table;
+
+ assert(tb->size != 0);
+ table = g_try_new(uint64_t, tb->size);
+ if (table == NULL) {
+ return -ENOMEM;
+ }
+
+ assert(tb->size <= BME_MAX_TABLE_SIZE);
+ ret = bdrv_pread(bs->file, tb->offset,
+ table, tb->size * sizeof(uint64_t));
+ if (ret < 0) {
+ goto fail;
+ }
+
+ for (i = 0; i < tb->size; ++i) {
+ be64_to_cpus(&table[i]);
+ ret = check_table_entry(table[i], s->cluster_size);
+ if (ret < 0) {
+ goto fail;
+ }
+ }
+
+ *bitmap_table = table;
+ return 0;
+
+fail:
+ g_free(table);
+
+ return ret;
+}
+
+/*
+ * Bitmap List
+ */
+
+/*
+ * Bitmap List private functions
+ * Only Bitmap List knows about bitmap directory structure in Qcow2.
+ */
+
+static inline void bitmap_dir_entry_to_cpu(Qcow2BitmapDirEntry *entry)
+{
+ be64_to_cpus(&entry->bitmap_table_offset);
+ be32_to_cpus(&entry->bitmap_table_size);
+ be32_to_cpus(&entry->flags);
+ be16_to_cpus(&entry->name_size);
+ be32_to_cpus(&entry->extra_data_size);
+}
+
+static inline int calc_dir_entry_size(size_t name_size, size_t extra_data_size)
+{
+ return align_offset(sizeof(Qcow2BitmapDirEntry) +
+ name_size + extra_data_size, 8);
+}
+
+static inline int dir_entry_size(Qcow2BitmapDirEntry *entry)
+{
+ return calc_dir_entry_size(entry->name_size, entry->extra_data_size);
+}
+
+static inline const char *dir_entry_name_field(Qcow2BitmapDirEntry *entry)
+{
+ return (const char *)(entry + 1) + entry->extra_data_size;
+}
+
+static inline char *dir_entry_copy_name(Qcow2BitmapDirEntry *entry)
+{
+ const char *name_field = dir_entry_name_field(entry);
+ return g_strndup(name_field, entry->name_size);
+}
+
+static inline Qcow2BitmapDirEntry *next_dir_entry(Qcow2BitmapDirEntry *entry)
+{
+ return (Qcow2BitmapDirEntry *)((uint8_t *)entry + dir_entry_size(entry));
+}
+
+static int check_dir_entry(BlockDriverState *bs, Qcow2BitmapDirEntry *entry)
+{
+ BDRVQcow2State *s = bs->opaque;
+ uint64_t phys_bitmap_bytes;
+ int64_t len;
+
+ bool fail = (entry->bitmap_table_size == 0) ||
+ (entry->bitmap_table_offset == 0) ||
+ (entry->bitmap_table_offset % s->cluster_size) ||
+ (entry->bitmap_table_size > BME_MAX_TABLE_SIZE) ||
+ (entry->granularity_bits > BME_MAX_GRANULARITY_BITS) ||
+ (entry->granularity_bits < BME_MIN_GRANULARITY_BITS) ||
+ (entry->flags & BME_RESERVED_FLAGS) ||
+ (entry->name_size > BME_MAX_NAME_SIZE) ||
+ (entry->type != BT_DIRTY_TRACKING_BITMAP);
+
+ if (fail) {
+ return -EINVAL;
+ }
+
+ phys_bitmap_bytes = (uint64_t)entry->bitmap_table_size * s->cluster_size;
+ len = bdrv_getlength(bs);
+
+ if (len < 0) {
+ return len;
+ }
+
+ fail = (phys_bitmap_bytes > BME_MAX_PHYS_SIZE) ||
+ (len > ((phys_bitmap_bytes * 8) << entry->granularity_bits));
+
+ return fail ? -EINVAL : 0;
+}
+
+/*
+ * Bitmap List public functions
+ */
+
+static void bitmap_free(Qcow2Bitmap *bm)
+{
+ g_free(bm->name);
+ g_free(bm);
+}
+
+static void bitmap_list_free(Qcow2BitmapList *bm_list)
+{
+ Qcow2Bitmap *bm;
+
+ if (bm_list == NULL) {
+ return;
+ }
+
+ while ((bm = QSIMPLEQ_FIRST(bm_list)) != NULL) {
+ QSIMPLEQ_REMOVE_HEAD(bm_list, entry);
+ bitmap_free(bm);
+ }
+
+ g_free(bm_list);
+}
+
+static Qcow2BitmapList *bitmap_list_new(void)
+{
+ Qcow2BitmapList *bm_list = g_new(Qcow2BitmapList, 1);
+ QSIMPLEQ_INIT(bm_list);
+
+ return bm_list;
+}
+
+/* bitmap_list_load
+ * Get bitmap list from qcow2 image. Actually reads bitmap directory,
+ * checks it and convert to bitmap list.
+ */
+static Qcow2BitmapList *bitmap_list_load(BlockDriverState *bs, uint64_t offset,
+ uint64_t size, Error **errp)
+{
+ int ret;
+ BDRVQcow2State *s = bs->opaque;
+ uint8_t *dir, *dir_end;
+ Qcow2BitmapDirEntry *e;
+ uint32_t nb_dir_entries = 0;
+ Qcow2BitmapList *bm_list = NULL;
+
+ if (size == 0) {
+ error_setg(errp, "Requested bitmap directory size is zero");
+ return NULL;
+ }
+
+ if (size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) {
+ error_setg(errp, "Requested bitmap directory size is too big");
+ return NULL;
+ }
+
+ dir = g_try_malloc(size);
+ if (dir == NULL) {
+ error_setg(errp, "Failed to allocate space for bitmap directory");
+ return NULL;
+ }
+ dir_end = dir + size;
+
+ ret = bdrv_pread(bs->file, offset, dir, size);
+ if (ret < 0) {
+ error_setg_errno(errp, -ret, "Failed to read bitmap directory");
+ goto fail;
+ }
+
+ bm_list = bitmap_list_new();
+ for (e = (Qcow2BitmapDirEntry *)dir;
+ e < (Qcow2BitmapDirEntry *)dir_end;
+ e = next_dir_entry(e))
+ {
+ Qcow2Bitmap *bm;
+
+ if ((uint8_t *)(e + 1) > dir_end) {
+ goto broken_dir;
+ }
+
+ if (++nb_dir_entries > s->nb_bitmaps) {
+ error_setg(errp, "More bitmaps found than specified in header"
+ " extension");
+ goto fail;
+ }
+ bitmap_dir_entry_to_cpu(e);
+
+ if ((uint8_t *)next_dir_entry(e) > dir_end) {
+ goto broken_dir;
+ }
+
+ if (e->extra_data_size != 0) {
+ error_setg(errp, "Bitmap extra data is not supported");
+ goto fail;
+ }
+
+ ret = check_dir_entry(bs, e);
+ if (ret < 0) {
+ error_setg(errp, "Bitmap '%.*s' doesn't satisfy the constraints",
+ e->name_size, dir_entry_name_field(e));
+ goto fail;
+ }
+
+ bm = g_new(Qcow2Bitmap, 1);
+ bm->table.offset = e->bitmap_table_offset;
+ bm->table.size = e->bitmap_table_size;
+ bm->flags = e->flags;
+ bm->granularity_bits = e->granularity_bits;
+ bm->name = dir_entry_copy_name(e);
+ QSIMPLEQ_INSERT_TAIL(bm_list, bm, entry);
+ }
+
+ if (nb_dir_entries != s->nb_bitmaps) {
+ error_setg(errp, "Less bitmaps found than specified in header"
+ " extension");
+ goto fail;
+ }
+
+ if ((uint8_t *)e != dir_end) {
+ goto broken_dir;
+ }
+
+ g_free(dir);
+ return bm_list;
+
+broken_dir:
+ ret = -EINVAL;
+ error_setg(errp, "Broken bitmap directory");
+
+fail:
+ g_free(dir);
+ bitmap_list_free(bm_list);
+
+ return NULL;
+}
+
+int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
+ void **refcount_table,
+ int64_t *refcount_table_size)
+{
+ int ret;
+ BDRVQcow2State *s = bs->opaque;
+ Qcow2BitmapList *bm_list;
+ Qcow2Bitmap *bm;
+
+ if (s->nb_bitmaps == 0) {
+ return 0;
+ }
+
+ ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table, refcount_table_size,
+ s->bitmap_directory_offset,
+ s->bitmap_directory_size);
+ if (ret < 0) {
+ return ret;
+ }
+
+ bm_list = bitmap_list_load(bs, s->bitmap_directory_offset,
+ s->bitmap_directory_size, NULL);
+ if (bm_list == NULL) {
+ res->corruptions++;
+ return -EINVAL;
+ }
+
+ QSIMPLEQ_FOREACH(bm, bm_list, entry) {
+ uint64_t *bitmap_table = NULL;
+ int i;
+
+ ret = qcow2_inc_refcounts_imrt(bs, res,
+ refcount_table, refcount_table_size,
+ bm->table.offset,
+ bm->table.size * sizeof(uint64_t));
+ if (ret < 0) {
+ goto out;
+ }
+
+ ret = bitmap_table_load(bs, &bm->table, &bitmap_table);
+ if (ret < 0) {
+ res->corruptions++;
+ goto out;
+ }
+
+ for (i = 0; i < bm->table.size; ++i) {
+ uint64_t entry = bitmap_table[i];
+ uint64_t offset = entry & BME_TABLE_ENTRY_OFFSET_MASK;
+
+ if (check_table_entry(entry, s->cluster_size) < 0) {
+ res->corruptions++;
+ continue;
+ }
+
+ if (offset == 0) {
+ continue;
+ }
+
+ ret = qcow2_inc_refcounts_imrt(bs, res,
+ refcount_table, refcount_table_size,
+ offset, s->cluster_size);
+ if (ret < 0) {
+ g_free(bitmap_table);
+ goto out;
+ }
+ }
+
+ g_free(bitmap_table);
+ }
+
+out:
+ bitmap_list_free(bm_list);
+
+ return ret;
+}
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index 8add3d5640..ceb08bc16f 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -1869,6 +1869,12 @@ static int calculate_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
}
}
+ /* bitmaps */
+ ret = qcow2_check_bitmaps_refcounts(bs, res, refcount_table, nb_clusters);
+ if (ret < 0) {
+ return ret;
+ }
+
return check_refblocks(bs, res, fix, rebuild, refcount_table, nb_clusters);
}
diff --git a/block/qcow2.c b/block/qcow2.c
index 5339aa0cb1..8688fdd8eb 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -67,6 +67,7 @@ typedef struct {
#define QCOW2_EXT_MAGIC_BACKING_FORMAT 0xE2792ACA
#define QCOW2_EXT_MAGIC_FEATURE_TABLE 0x6803f857
#define QCOW2_EXT_MAGIC_CRYPTO_HEADER 0x0537be77
+#define QCOW2_EXT_MAGIC_BITMAPS 0x23852875
static int qcow2_probe(const uint8_t *buf, int buf_size, const char *filename)
{
@@ -170,12 +171,18 @@ static ssize_t qcow2_crypto_hdr_write_func(QCryptoBlock *block, size_t offset,
*/
static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset,
uint64_t end_offset, void **p_feature_table,
- int flags, Error **errp)
+ int flags, bool *need_update_header,
+ Error **errp)
{
BDRVQcow2State *s = bs->opaque;
QCowExtension ext;
uint64_t offset;
int ret;
+ Qcow2BitmapHeaderExt bitmaps_ext;
+
+ if (need_update_header != NULL) {
+ *need_update_header = false;
+ }
#ifdef DEBUG_EXT
printf("qcow2_read_extensions: start=%ld end=%ld\n", start_offset, end_offset);
@@ -287,6 +294,85 @@ static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset,
}
} break;
+ case QCOW2_EXT_MAGIC_BITMAPS:
+ if (ext.len != sizeof(bitmaps_ext)) {
+ error_setg_errno(errp, -ret, "bitmaps_ext: "
+ "Invalid extension length");
+ return -EINVAL;
+ }
+
+ if (!(s->autoclear_features & QCOW2_AUTOCLEAR_BITMAPS)) {
+ error_report("WARNING: a program lacking bitmap support "
+ "modified this file, so all bitmaps are now "
+ "considered inconsistent. Some clusters may be "
+ "leaked, run 'qemu-img check -r' on the image "
+ "file to fix.");
+ if (need_update_header != NULL) {
+ /* Updating is needed to drop invalid bitmap extension. */
+ *need_update_header = true;
+ }
+ break;
+ }
+
+ ret = bdrv_pread(bs->file, offset, &bitmaps_ext, ext.len);
+ if (ret < 0) {
+ error_setg_errno(errp, -ret, "bitmaps_ext: "
+ "Could not read ext header");
+ return ret;
+ }
+
+ if (bitmaps_ext.reserved32 != 0) {
+ error_setg_errno(errp, -ret, "bitmaps_ext: "
+ "Reserved field is not zero");
+ return -EINVAL;
+ }
+
+ be32_to_cpus(&bitmaps_ext.nb_bitmaps);
+ be64_to_cpus(&bitmaps_ext.bitmap_directory_size);
+ be64_to_cpus(&bitmaps_ext.bitmap_directory_offset);
+
+ if (bitmaps_ext.nb_bitmaps > QCOW2_MAX_BITMAPS) {
+ error_setg(errp,
+ "bitmaps_ext: Image has %" PRIu32 " bitmaps, "
+ "exceeding the QEMU supported maximum of %d",
+ bitmaps_ext.nb_bitmaps, QCOW2_MAX_BITMAPS);
+ return -EINVAL;
+ }
+
+ if (bitmaps_ext.nb_bitmaps == 0) {
+ error_setg(errp, "found bitmaps extension with zero bitmaps");
+ return -EINVAL;
+ }
+
+ if (bitmaps_ext.bitmap_directory_offset & (s->cluster_size - 1)) {
+ error_setg(errp, "bitmaps_ext: "
+ "invalid bitmap directory offset");
+ return -EINVAL;
+ }
+
+ if (bitmaps_ext.bitmap_directory_size >
+ QCOW2_MAX_BITMAP_DIRECTORY_SIZE) {
+ error_setg(errp, "bitmaps_ext: "
+ "bitmap directory size (%" PRIu64 ") exceeds "
+ "the maximum supported size (%d)",
+ bitmaps_ext.bitmap_directory_size,
+ QCOW2_MAX_BITMAP_DIRECTORY_SIZE);
+ return -EINVAL;
+ }
+
+ s->nb_bitmaps = bitmaps_ext.nb_bitmaps;
+ s->bitmap_directory_offset =
+ bitmaps_ext.bitmap_directory_offset;
+ s->bitmap_directory_size =
+ bitmaps_ext.bitmap_directory_size;
+
+#ifdef DEBUG_EXT
+ printf("Qcow2: Got bitmaps extension: "
+ "offset=%" PRIu64 " nb_bitmaps=%" PRIu32 "\n",
+ s->bitmap_directory_offset, s->nb_bitmaps);
+#endif
+ break;
+
default:
/* unknown magic - save it in case we need to rewrite the header */
{
@@ -1008,6 +1094,7 @@ static int qcow2_do_open(BlockDriverState *bs, QDict *options, int flags,
Error *local_err = NULL;
uint64_t ext_end;
uint64_t l1_vm_state_index;
+ bool update_header = false;
ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
if (ret < 0) {
@@ -1113,7 +1200,7 @@ static int qcow2_do_open(BlockDriverState *bs, QDict *options, int flags,
if (s->incompatible_features & ~QCOW2_INCOMPAT_MASK) {
void *feature_table = NULL;
qcow2_read_extensions(bs, header.header_length, ext_end,
- &feature_table, flags, NULL);
+ &feature_table, flags, NULL, NULL);
report_unsupported_feature(errp, feature_table,
s->incompatible_features &
~QCOW2_INCOMPAT_MASK);
@@ -1297,7 +1384,7 @@ static int qcow2_do_open(BlockDriverState *bs, QDict *options, int flags,
/* read qcow2 extensions */
if (qcow2_read_extensions(bs, header.header_length, ext_end, NULL,
- flags, &local_err)) {
+ flags, &update_header, &local_err)) {
error_propagate(errp, local_err);
ret = -EINVAL;
goto fail;
@@ -1357,8 +1444,10 @@ static int qcow2_do_open(BlockDriverState *bs, QDict *options, int flags,
}
/* Clear unknown autoclear feature bits */
- if (!bs->read_only && !(flags & BDRV_O_INACTIVE) && s->autoclear_features) {
- s->autoclear_features = 0;
+ update_header |= s->autoclear_features & ~QCOW2_AUTOCLEAR_MASK;
+
+ if (update_header && !bs->read_only && !(flags & BDRV_O_INACTIVE)) {
+ s->autoclear_features &= QCOW2_AUTOCLEAR_MASK;
ret = qcow2_update_header(bs);
if (ret < 0) {
error_setg_errno(errp, -ret, "Could not update qcow2 header");
@@ -2203,6 +2292,25 @@ int qcow2_update_header(BlockDriverState *bs)
buflen -= ret;
}
+ /* Bitmap extension */
+ if (s->nb_bitmaps > 0) {
+ Qcow2BitmapHeaderExt bitmaps_header = {
+ .nb_bitmaps = cpu_to_be32(s->nb_bitmaps),
+ .bitmap_directory_size =
+ cpu_to_be64(s->bitmap_directory_size),
+ .bitmap_directory_offset =
+ cpu_to_be64(s->bitmap_directory_offset)
+ };
+ ret = header_ext_add(buf, QCOW2_EXT_MAGIC_BITMAPS,
+ &bitmaps_header, sizeof(bitmaps_header),
+ buflen);
+ if (ret < 0) {
+ goto fail;
+ }
+ buf += ret;
+ buflen -= ret;
+ }
+
/* Keep unknown header extensions */
QLIST_FOREACH(uext, &s->unknown_header_ext, next) {
ret = header_ext_add(buf, uext->magic, uext->data, uext->len, buflen);
@@ -2884,6 +2992,13 @@ static int qcow2_truncate(BlockDriverState *bs, int64_t offset, Error **errp)
return -ENOTSUP;
}
+ /* cannot proceed if image has bitmaps */
+ if (s->nb_bitmaps) {
+ /* TODO: resize bitmaps in the image */
+ error_setg(errp, "Can't resize an image which has bitmaps");
+ return -ENOTSUP;
+ }
+
/* shrinking is currently not supported */
if (offset < bs->total_sectors * 512) {
error_setg(errp, "qcow2 doesn't support shrinking images yet");
diff --git a/block/qcow2.h b/block/qcow2.h
index a272a39ab2..348864860b 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -53,6 +53,10 @@
* space for snapshot names and IDs */
#define QCOW_MAX_SNAPSHOTS_SIZE (1024 * QCOW_MAX_SNAPSHOTS)
+/* Bitmap header extension constraints */
+#define QCOW2_MAX_BITMAPS 65535
+#define QCOW2_MAX_BITMAP_DIRECTORY_SIZE (1024 * QCOW2_MAX_BITMAPS)
+
/* indicate that the refcount of the referenced cluster is exactly one. */
#define QCOW_OFLAG_COPIED (1ULL << 63)
/* indicate that the cluster is compressed (they never have the copied flag) */
@@ -201,6 +205,14 @@ enum {
QCOW2_COMPAT_FEAT_MASK = QCOW2_COMPAT_LAZY_REFCOUNTS,
};
+/* Autoclear feature bits */
+enum {
+ QCOW2_AUTOCLEAR_BITMAPS_BITNR = 0,
+ QCOW2_AUTOCLEAR_BITMAPS = 1 << QCOW2_AUTOCLEAR_BITMAPS_BITNR,
+
+ QCOW2_AUTOCLEAR_MASK = QCOW2_AUTOCLEAR_BITMAPS,
+};
+
enum qcow2_discard_type {
QCOW2_DISCARD_NEVER = 0,
QCOW2_DISCARD_ALWAYS,
@@ -228,6 +240,13 @@ typedef uint64_t Qcow2GetRefcountFunc(const void *refcount_array,
typedef void Qcow2SetRefcountFunc(void *refcount_array,
uint64_t index, uint64_t value);
+typedef struct Qcow2BitmapHeaderExt {
+ uint32_t nb_bitmaps;
+ uint32_t reserved32;
+ uint64_t bitmap_directory_size;
+ uint64_t bitmap_directory_offset;
+} QEMU_PACKED Qcow2BitmapHeaderExt;
+
typedef struct BDRVQcow2State {
int cluster_bits;
int cluster_size;
@@ -274,6 +293,10 @@ typedef struct BDRVQcow2State {
unsigned int nb_snapshots;
QCowSnapshot *snapshots;
+ uint32_t nb_bitmaps;
+ uint64_t bitmap_directory_size;
+ uint64_t bitmap_directory_offset;
+
int flags;
int qcow_version;
bool use_lazy_refcounts;
@@ -618,4 +641,8 @@ int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
void **table);
void qcow2_cache_put(BlockDriverState *bs, 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);
#endif