When pulling in headers that are in the same directory as the C file (as opposed to one in include/), we should use its relative path, without a directory. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
1518 lines
42 KiB
C
1518 lines
42 KiB
C
/*
|
|
* Bitmaps for the QCOW version 2 format
|
|
*
|
|
* Copyright (c) 2014-2017 Vladimir Sementsov-Ogievskiy
|
|
*
|
|
* This file is derived from qcow2-snapshot.c, original copyright:
|
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* Copyright (c) 2004-2006 Fabrice Bellard
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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|
* in the Software without restriction, including without limitation the rights
|
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* 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:
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*
|
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* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
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*
|
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* 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
|
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* 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,
|
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* 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 "qemu/cutils.h"
|
|
|
|
#include "block/block_int.h"
|
|
#include "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
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|
|
|
#if BME_MAX_TABLE_SIZE * 8ULL > INT_MAX
|
|
#error In the code bitmap table physical size assumed to fit into int
|
|
#endif
|
|
|
|
/* Bitmap directory entry flags */
|
|
#define BME_RESERVED_FLAGS 0xfffffffcU
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|
#define BME_FLAG_IN_USE (1U << 0)
|
|
#define BME_FLAG_AUTO (1U << 1)
|
|
|
|
/* bits [1, 8] U [56, 63] are reserved */
|
|
#define BME_TABLE_ENTRY_RESERVED_MASK 0xff000000000001feULL
|
|
#define BME_TABLE_ENTRY_OFFSET_MASK 0x00fffffffffffe00ULL
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#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;
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|
|
|
typedef struct Qcow2BitmapTable {
|
|
uint64_t offset;
|
|
uint32_t size; /* number of 64bit entries */
|
|
QSIMPLEQ_ENTRY(Qcow2BitmapTable) entry;
|
|
} Qcow2BitmapTable;
|
|
typedef QSIMPLEQ_HEAD(Qcow2BitmapTableList, Qcow2BitmapTable)
|
|
Qcow2BitmapTableList;
|
|
|
|
typedef struct Qcow2Bitmap {
|
|
Qcow2BitmapTable table;
|
|
uint32_t flags;
|
|
uint8_t granularity_bits;
|
|
char *name;
|
|
|
|
BdrvDirtyBitmap *dirty_bitmap;
|
|
|
|
QSIMPLEQ_ENTRY(Qcow2Bitmap) entry;
|
|
} Qcow2Bitmap;
|
|
typedef QSIMPLEQ_HEAD(Qcow2BitmapList, Qcow2Bitmap) Qcow2BitmapList;
|
|
|
|
typedef enum BitmapType {
|
|
BT_DIRTY_TRACKING_BITMAP = 1
|
|
} BitmapType;
|
|
|
|
static inline bool can_write(BlockDriverState *bs)
|
|
{
|
|
return !bdrv_is_read_only(bs) && !(bdrv_get_flags(bs) & BDRV_O_INACTIVE);
|
|
}
|
|
|
|
static int update_header_sync(BlockDriverState *bs)
|
|
{
|
|
int ret;
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|
|
|
ret = qcow2_update_header(bs);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
return bdrv_flush(bs->file->bs);
|
|
}
|
|
|
|
static inline void bitmap_table_to_be(uint64_t *bitmap_table, size_t size)
|
|
{
|
|
size_t i;
|
|
|
|
for (i = 0; i < size; ++i) {
|
|
cpu_to_be64s(&bitmap_table[i]);
|
|
}
|
|
}
|
|
|
|
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 check_constraints_on_bitmap(BlockDriverState *bs,
|
|
const char *name,
|
|
uint32_t granularity,
|
|
Error **errp)
|
|
{
|
|
BDRVQcow2State *s = bs->opaque;
|
|
int granularity_bits = ctz32(granularity);
|
|
int64_t len = bdrv_getlength(bs);
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|
|
|
assert(granularity > 0);
|
|
assert((granularity & (granularity - 1)) == 0);
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|
|
|
if (len < 0) {
|
|
error_setg_errno(errp, -len, "Failed to get size of '%s'",
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bdrv_get_device_or_node_name(bs));
|
|
return len;
|
|
}
|
|
|
|
if (granularity_bits > BME_MAX_GRANULARITY_BITS) {
|
|
error_setg(errp, "Granularity exceeds maximum (%llu bytes)",
|
|
1ULL << BME_MAX_GRANULARITY_BITS);
|
|
return -EINVAL;
|
|
}
|
|
if (granularity_bits < BME_MIN_GRANULARITY_BITS) {
|
|
error_setg(errp, "Granularity is under minimum (%llu bytes)",
|
|
1ULL << BME_MIN_GRANULARITY_BITS);
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|
return -EINVAL;
|
|
}
|
|
|
|
if ((len > (uint64_t)BME_MAX_PHYS_SIZE << granularity_bits) ||
|
|
(len > (uint64_t)BME_MAX_TABLE_SIZE * s->cluster_size <<
|
|
granularity_bits))
|
|
{
|
|
error_setg(errp, "Too much space will be occupied by the bitmap. "
|
|
"Use larger granularity");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (strlen(name) > BME_MAX_NAME_SIZE) {
|
|
error_setg(errp, "Name length exceeds maximum (%u characters)",
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|
BME_MAX_NAME_SIZE);
|
|
return -EINVAL;
|
|
}
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|
|
|
return 0;
|
|
}
|
|
|
|
static void clear_bitmap_table(BlockDriverState *bs, uint64_t *bitmap_table,
|
|
uint32_t bitmap_table_size)
|
|
{
|
|
BDRVQcow2State *s = bs->opaque;
|
|
int i;
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|
|
|
for (i = 0; i < bitmap_table_size; ++i) {
|
|
uint64_t addr = bitmap_table[i] & BME_TABLE_ENTRY_OFFSET_MASK;
|
|
if (!addr) {
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|
continue;
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|
}
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|
|
|
qcow2_free_clusters(bs, addr, s->cluster_size, QCOW2_DISCARD_OTHER);
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|
bitmap_table[i] = 0;
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|
}
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|
}
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|
|
static int bitmap_table_load(BlockDriverState *bs, Qcow2BitmapTable *tb,
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uint64_t **bitmap_table)
|
|
{
|
|
int ret;
|
|
BDRVQcow2State *s = bs->opaque;
|
|
uint32_t i;
|
|
uint64_t *table;
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|
|
|
assert(tb->size != 0);
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|
table = g_try_new(uint64_t, tb->size);
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if (table == NULL) {
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return -ENOMEM;
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}
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|
|
assert(tb->size <= BME_MAX_TABLE_SIZE);
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ret = bdrv_pread(bs->file, tb->offset,
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table, tb->size * sizeof(uint64_t));
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if (ret < 0) {
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goto fail;
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}
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for (i = 0; i < tb->size; ++i) {
|
|
be64_to_cpus(&table[i]);
|
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ret = check_table_entry(table[i], s->cluster_size);
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|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
}
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|
|
|
*bitmap_table = table;
|
|
return 0;
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|
|
|
fail:
|
|
g_free(table);
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|
|
|
return ret;
|
|
}
|
|
|
|
static int free_bitmap_clusters(BlockDriverState *bs, Qcow2BitmapTable *tb)
|
|
{
|
|
int ret;
|
|
uint64_t *bitmap_table;
|
|
|
|
ret = bitmap_table_load(bs, tb, &bitmap_table);
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if (ret < 0) {
|
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assert(bitmap_table == NULL);
|
|
return ret;
|
|
}
|
|
|
|
clear_bitmap_table(bs, bitmap_table, tb->size);
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qcow2_free_clusters(bs, tb->offset, tb->size * sizeof(uint64_t),
|
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QCOW2_DISCARD_OTHER);
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g_free(bitmap_table);
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|
|
|
tb->offset = 0;
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|
tb->size = 0;
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|
|
|
return 0;
|
|
}
|
|
|
|
/* Return the disk size covered by a single qcow2 cluster of bitmap data. */
|
|
static uint64_t bytes_covered_by_bitmap_cluster(const BDRVQcow2State *s,
|
|
const BdrvDirtyBitmap *bitmap)
|
|
{
|
|
uint64_t granularity = bdrv_dirty_bitmap_granularity(bitmap);
|
|
uint64_t limit = granularity * (s->cluster_size << 3);
|
|
|
|
assert(QEMU_IS_ALIGNED(limit,
|
|
bdrv_dirty_bitmap_serialization_align(bitmap)));
|
|
return limit;
|
|
}
|
|
|
|
/* load_bitmap_data
|
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* @bitmap_table entries must satisfy specification constraints.
|
|
* @bitmap must be cleared */
|
|
static int load_bitmap_data(BlockDriverState *bs,
|
|
const uint64_t *bitmap_table,
|
|
uint32_t bitmap_table_size,
|
|
BdrvDirtyBitmap *bitmap)
|
|
{
|
|
int ret = 0;
|
|
BDRVQcow2State *s = bs->opaque;
|
|
uint64_t offset, limit;
|
|
uint64_t bm_size = bdrv_dirty_bitmap_size(bitmap);
|
|
uint8_t *buf = NULL;
|
|
uint64_t i, tab_size =
|
|
size_to_clusters(s,
|
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bdrv_dirty_bitmap_serialization_size(bitmap, 0, bm_size));
|
|
|
|
if (tab_size != bitmap_table_size || tab_size > BME_MAX_TABLE_SIZE) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
buf = g_malloc(s->cluster_size);
|
|
limit = bytes_covered_by_bitmap_cluster(s, bitmap);
|
|
for (i = 0, offset = 0; i < tab_size; ++i, offset += limit) {
|
|
uint64_t count = MIN(bm_size - offset, limit);
|
|
uint64_t entry = bitmap_table[i];
|
|
uint64_t data_offset = entry & BME_TABLE_ENTRY_OFFSET_MASK;
|
|
|
|
assert(check_table_entry(entry, s->cluster_size) == 0);
|
|
|
|
if (data_offset == 0) {
|
|
if (entry & BME_TABLE_ENTRY_FLAG_ALL_ONES) {
|
|
bdrv_dirty_bitmap_deserialize_ones(bitmap, offset, count,
|
|
false);
|
|
} else {
|
|
/* No need to deserialize zeros because the dirty bitmap is
|
|
* already cleared */
|
|
}
|
|
} else {
|
|
ret = bdrv_pread(bs->file, data_offset, buf, s->cluster_size);
|
|
if (ret < 0) {
|
|
goto finish;
|
|
}
|
|
bdrv_dirty_bitmap_deserialize_part(bitmap, buf, offset, count,
|
|
false);
|
|
}
|
|
}
|
|
ret = 0;
|
|
|
|
bdrv_dirty_bitmap_deserialize_finish(bitmap);
|
|
|
|
finish:
|
|
g_free(buf);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static BdrvDirtyBitmap *load_bitmap(BlockDriverState *bs,
|
|
Qcow2Bitmap *bm, Error **errp)
|
|
{
|
|
int ret;
|
|
uint64_t *bitmap_table = NULL;
|
|
uint32_t granularity;
|
|
BdrvDirtyBitmap *bitmap = NULL;
|
|
|
|
if (bm->flags & BME_FLAG_IN_USE) {
|
|
error_setg(errp, "Bitmap '%s' is in use", bm->name);
|
|
goto fail;
|
|
}
|
|
|
|
ret = bitmap_table_load(bs, &bm->table, &bitmap_table);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret,
|
|
"Could not read bitmap_table table from image for "
|
|
"bitmap '%s'", bm->name);
|
|
goto fail;
|
|
}
|
|
|
|
granularity = 1U << bm->granularity_bits;
|
|
bitmap = bdrv_create_dirty_bitmap(bs, granularity, bm->name, errp);
|
|
if (bitmap == NULL) {
|
|
goto fail;
|
|
}
|
|
|
|
ret = load_bitmap_data(bs, bitmap_table, bm->table.size, bitmap);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Could not read bitmap '%s' from image",
|
|
bm->name);
|
|
goto fail;
|
|
}
|
|
|
|
g_free(bitmap_table);
|
|
return bitmap;
|
|
|
|
fail:
|
|
g_free(bitmap_table);
|
|
if (bitmap != NULL) {
|
|
bdrv_release_dirty_bitmap(bs, bitmap);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* 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 void bitmap_dir_entry_to_be(Qcow2BitmapDirEntry *entry)
|
|
{
|
|
cpu_to_be64s(&entry->bitmap_table_offset);
|
|
cpu_to_be32s(&entry->bitmap_table_size);
|
|
cpu_to_be32s(&entry->flags);
|
|
cpu_to_be16s(&entry->name_size);
|
|
cpu_to_be32s(&entry->extra_data_size);
|
|
}
|
|
|
|
static inline int calc_dir_entry_size(size_t name_size, size_t extra_data_size)
|
|
{
|
|
int size = sizeof(Qcow2BitmapDirEntry) + name_size + extra_data_size;
|
|
return ROUND_UP(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;
|
|
}
|
|
|
|
static inline void bitmap_directory_to_be(uint8_t *dir, size_t size)
|
|
{
|
|
uint8_t *end = dir + size;
|
|
while (dir < end) {
|
|
Qcow2BitmapDirEntry *e = (Qcow2BitmapDirEntry *)dir;
|
|
dir += dir_entry_size(e);
|
|
|
|
bitmap_dir_entry_to_be(e);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Bitmap List public functions
|
|
*/
|
|
|
|
static void bitmap_free(Qcow2Bitmap *bm)
|
|
{
|
|
if (bm == NULL) {
|
|
return;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
static uint32_t bitmap_list_count(Qcow2BitmapList *bm_list)
|
|
{
|
|
Qcow2Bitmap *bm;
|
|
uint32_t nb_bitmaps = 0;
|
|
|
|
QSIMPLEQ_FOREACH(bm, bm_list, entry) {
|
|
nb_bitmaps++;
|
|
}
|
|
|
|
return nb_bitmaps;
|
|
}
|
|
|
|
/* 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_new0(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;
|
|
}
|
|
|
|
/* bitmap_list_store
|
|
* Store bitmap list to qcow2 image as a bitmap directory.
|
|
* Everything is checked.
|
|
*/
|
|
static int bitmap_list_store(BlockDriverState *bs, Qcow2BitmapList *bm_list,
|
|
uint64_t *offset, uint64_t *size, bool in_place)
|
|
{
|
|
int ret;
|
|
uint8_t *dir;
|
|
int64_t dir_offset = 0;
|
|
uint64_t dir_size = 0;
|
|
Qcow2Bitmap *bm;
|
|
Qcow2BitmapDirEntry *e;
|
|
|
|
QSIMPLEQ_FOREACH(bm, bm_list, entry) {
|
|
dir_size += calc_dir_entry_size(strlen(bm->name), 0);
|
|
}
|
|
|
|
if (dir_size == 0 || dir_size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (in_place) {
|
|
if (*size != dir_size || *offset == 0) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
dir_offset = *offset;
|
|
}
|
|
|
|
dir = g_try_malloc(dir_size);
|
|
if (dir == NULL) {
|
|
return -ENOMEM;
|
|
}
|
|
|
|
e = (Qcow2BitmapDirEntry *)dir;
|
|
QSIMPLEQ_FOREACH(bm, bm_list, entry) {
|
|
e->bitmap_table_offset = bm->table.offset;
|
|
e->bitmap_table_size = bm->table.size;
|
|
e->flags = bm->flags;
|
|
e->type = BT_DIRTY_TRACKING_BITMAP;
|
|
e->granularity_bits = bm->granularity_bits;
|
|
e->name_size = strlen(bm->name);
|
|
e->extra_data_size = 0;
|
|
memcpy(e + 1, bm->name, e->name_size);
|
|
|
|
if (check_dir_entry(bs, e) < 0) {
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
e = next_dir_entry(e);
|
|
}
|
|
|
|
bitmap_directory_to_be(dir, dir_size);
|
|
|
|
if (!in_place) {
|
|
dir_offset = qcow2_alloc_clusters(bs, dir_size);
|
|
if (dir_offset < 0) {
|
|
ret = dir_offset;
|
|
goto fail;
|
|
}
|
|
}
|
|
|
|
ret = qcow2_pre_write_overlap_check(bs, 0, dir_offset, dir_size);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
|
|
ret = bdrv_pwrite(bs->file, dir_offset, dir, dir_size);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
|
|
g_free(dir);
|
|
|
|
if (!in_place) {
|
|
*size = dir_size;
|
|
*offset = dir_offset;
|
|
}
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
g_free(dir);
|
|
|
|
if (!in_place && dir_offset > 0) {
|
|
qcow2_free_clusters(bs, dir_offset, dir_size, QCOW2_DISCARD_OTHER);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Bitmap List end
|
|
*/
|
|
|
|
static int update_ext_header_and_dir_in_place(BlockDriverState *bs,
|
|
Qcow2BitmapList *bm_list)
|
|
{
|
|
BDRVQcow2State *s = bs->opaque;
|
|
int ret;
|
|
|
|
if (!(s->autoclear_features & QCOW2_AUTOCLEAR_BITMAPS) ||
|
|
bm_list == NULL || QSIMPLEQ_EMPTY(bm_list) ||
|
|
bitmap_list_count(bm_list) != s->nb_bitmaps)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
s->autoclear_features &= ~(uint64_t)QCOW2_AUTOCLEAR_BITMAPS;
|
|
ret = update_header_sync(bs);
|
|
if (ret < 0) {
|
|
/* Two variants are possible here:
|
|
* 1. Autoclear flag is dropped, all bitmaps will be lost.
|
|
* 2. Autoclear flag is not dropped, old state is left.
|
|
*/
|
|
return ret;
|
|
}
|
|
|
|
/* autoclear bit is not set, so we can safely update bitmap directory */
|
|
|
|
ret = bitmap_list_store(bs, bm_list, &s->bitmap_directory_offset,
|
|
&s->bitmap_directory_size, true);
|
|
if (ret < 0) {
|
|
/* autoclear bit is cleared, so all leaked clusters would be removed on
|
|
* qemu-img check */
|
|
return ret;
|
|
}
|
|
|
|
ret = update_header_sync(bs);
|
|
if (ret < 0) {
|
|
/* autoclear bit is cleared, so all leaked clusters would be removed on
|
|
* qemu-img check */
|
|
return ret;
|
|
}
|
|
|
|
s->autoclear_features |= QCOW2_AUTOCLEAR_BITMAPS;
|
|
return update_header_sync(bs);
|
|
/* If final update_header_sync() fails, two variants are possible:
|
|
* 1. Autoclear flag is not set, all bitmaps will be lost.
|
|
* 2. Autoclear flag is set, header and directory are successfully updated.
|
|
*/
|
|
}
|
|
|
|
static int update_ext_header_and_dir(BlockDriverState *bs,
|
|
Qcow2BitmapList *bm_list)
|
|
{
|
|
BDRVQcow2State *s = bs->opaque;
|
|
int ret;
|
|
uint64_t new_offset = 0;
|
|
uint64_t new_size = 0;
|
|
uint32_t new_nb_bitmaps = 0;
|
|
uint64_t old_offset = s->bitmap_directory_offset;
|
|
uint64_t old_size = s->bitmap_directory_size;
|
|
uint32_t old_nb_bitmaps = s->nb_bitmaps;
|
|
uint64_t old_autocl = s->autoclear_features;
|
|
|
|
if (bm_list != NULL && !QSIMPLEQ_EMPTY(bm_list)) {
|
|
new_nb_bitmaps = bitmap_list_count(bm_list);
|
|
|
|
if (new_nb_bitmaps > QCOW2_MAX_BITMAPS) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = bitmap_list_store(bs, bm_list, &new_offset, &new_size, false);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
ret = qcow2_flush_caches(bs);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
|
|
s->autoclear_features |= QCOW2_AUTOCLEAR_BITMAPS;
|
|
} else {
|
|
s->autoclear_features &= ~(uint64_t)QCOW2_AUTOCLEAR_BITMAPS;
|
|
}
|
|
|
|
s->bitmap_directory_offset = new_offset;
|
|
s->bitmap_directory_size = new_size;
|
|
s->nb_bitmaps = new_nb_bitmaps;
|
|
|
|
ret = update_header_sync(bs);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
|
|
if (old_size > 0) {
|
|
qcow2_free_clusters(bs, old_offset, old_size, QCOW2_DISCARD_OTHER);
|
|
}
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
if (new_offset > 0) {
|
|
qcow2_free_clusters(bs, new_offset, new_size, QCOW2_DISCARD_OTHER);
|
|
}
|
|
|
|
s->bitmap_directory_offset = old_offset;
|
|
s->bitmap_directory_size = old_size;
|
|
s->nb_bitmaps = old_nb_bitmaps;
|
|
s->autoclear_features = old_autocl;
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* for g_slist_foreach for GSList of BdrvDirtyBitmap* elements */
|
|
static void release_dirty_bitmap_helper(gpointer bitmap,
|
|
gpointer bs)
|
|
{
|
|
bdrv_release_dirty_bitmap(bs, bitmap);
|
|
}
|
|
|
|
/* for g_slist_foreach for GSList of BdrvDirtyBitmap* elements */
|
|
static void set_readonly_helper(gpointer bitmap, gpointer value)
|
|
{
|
|
bdrv_dirty_bitmap_set_readonly(bitmap, (bool)value);
|
|
}
|
|
|
|
/* qcow2_load_dirty_bitmaps()
|
|
* Return value is a hint for caller: true means that the Qcow2 header was
|
|
* updated. (false doesn't mean that the header should be updated by the
|
|
* caller, it just means that updating was not needed or the image cannot be
|
|
* written to).
|
|
* On failure the function returns false.
|
|
*/
|
|
bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp)
|
|
{
|
|
BDRVQcow2State *s = bs->opaque;
|
|
Qcow2BitmapList *bm_list;
|
|
Qcow2Bitmap *bm;
|
|
GSList *created_dirty_bitmaps = NULL;
|
|
bool header_updated = false;
|
|
|
|
if (s->nb_bitmaps == 0) {
|
|
/* No bitmaps - nothing to do */
|
|
return false;
|
|
}
|
|
|
|
bm_list = bitmap_list_load(bs, s->bitmap_directory_offset,
|
|
s->bitmap_directory_size, errp);
|
|
if (bm_list == NULL) {
|
|
return false;
|
|
}
|
|
|
|
QSIMPLEQ_FOREACH(bm, bm_list, entry) {
|
|
if (!(bm->flags & BME_FLAG_IN_USE)) {
|
|
BdrvDirtyBitmap *bitmap = load_bitmap(bs, bm, errp);
|
|
if (bitmap == NULL) {
|
|
goto fail;
|
|
}
|
|
|
|
if (!(bm->flags & BME_FLAG_AUTO)) {
|
|
bdrv_disable_dirty_bitmap(bitmap);
|
|
}
|
|
bdrv_dirty_bitmap_set_persistance(bitmap, true);
|
|
bm->flags |= BME_FLAG_IN_USE;
|
|
created_dirty_bitmaps =
|
|
g_slist_append(created_dirty_bitmaps, bitmap);
|
|
}
|
|
}
|
|
|
|
if (created_dirty_bitmaps != NULL) {
|
|
if (can_write(bs)) {
|
|
/* in_use flags must be updated */
|
|
int ret = update_ext_header_and_dir_in_place(bs, bm_list);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Can't update bitmap directory");
|
|
goto fail;
|
|
}
|
|
header_updated = true;
|
|
} else {
|
|
g_slist_foreach(created_dirty_bitmaps, set_readonly_helper,
|
|
(gpointer)true);
|
|
}
|
|
}
|
|
|
|
g_slist_free(created_dirty_bitmaps);
|
|
bitmap_list_free(bm_list);
|
|
|
|
return header_updated;
|
|
|
|
fail:
|
|
g_slist_foreach(created_dirty_bitmaps, release_dirty_bitmap_helper, bs);
|
|
g_slist_free(created_dirty_bitmaps);
|
|
bitmap_list_free(bm_list);
|
|
|
|
return false;
|
|
}
|
|
|
|
int qcow2_reopen_bitmaps_rw_hint(BlockDriverState *bs, bool *header_updated,
|
|
Error **errp)
|
|
{
|
|
BDRVQcow2State *s = bs->opaque;
|
|
Qcow2BitmapList *bm_list;
|
|
Qcow2Bitmap *bm;
|
|
GSList *ro_dirty_bitmaps = NULL;
|
|
int ret = 0;
|
|
|
|
if (header_updated != NULL) {
|
|
*header_updated = false;
|
|
}
|
|
|
|
if (s->nb_bitmaps == 0) {
|
|
/* No bitmaps - nothing to do */
|
|
return 0;
|
|
}
|
|
|
|
if (!can_write(bs)) {
|
|
error_setg(errp, "Can't write to the image on reopening bitmaps rw");
|
|
return -EINVAL;
|
|
}
|
|
|
|
bm_list = bitmap_list_load(bs, s->bitmap_directory_offset,
|
|
s->bitmap_directory_size, errp);
|
|
if (bm_list == NULL) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
QSIMPLEQ_FOREACH(bm, bm_list, entry) {
|
|
if (!(bm->flags & BME_FLAG_IN_USE)) {
|
|
BdrvDirtyBitmap *bitmap = bdrv_find_dirty_bitmap(bs, bm->name);
|
|
if (bitmap == NULL) {
|
|
continue;
|
|
}
|
|
|
|
if (!bdrv_dirty_bitmap_readonly(bitmap)) {
|
|
error_setg(errp, "Bitmap %s is not readonly but not marked"
|
|
"'IN_USE' in the image. Something went wrong,"
|
|
"all the bitmaps may be corrupted", bm->name);
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
bm->flags |= BME_FLAG_IN_USE;
|
|
ro_dirty_bitmaps = g_slist_append(ro_dirty_bitmaps, bitmap);
|
|
}
|
|
}
|
|
|
|
if (ro_dirty_bitmaps != NULL) {
|
|
/* in_use flags must be updated */
|
|
ret = update_ext_header_and_dir_in_place(bs, bm_list);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Can't update bitmap directory");
|
|
goto out;
|
|
}
|
|
if (header_updated != NULL) {
|
|
*header_updated = true;
|
|
}
|
|
g_slist_foreach(ro_dirty_bitmaps, set_readonly_helper, false);
|
|
}
|
|
|
|
out:
|
|
g_slist_free(ro_dirty_bitmaps);
|
|
bitmap_list_free(bm_list);
|
|
|
|
return ret;
|
|
}
|
|
|
|
int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp)
|
|
{
|
|
return qcow2_reopen_bitmaps_rw_hint(bs, NULL, errp);
|
|
}
|
|
|
|
/* store_bitmap_data()
|
|
* Store bitmap to image, filling bitmap table accordingly.
|
|
*/
|
|
static uint64_t *store_bitmap_data(BlockDriverState *bs,
|
|
BdrvDirtyBitmap *bitmap,
|
|
uint32_t *bitmap_table_size, Error **errp)
|
|
{
|
|
int ret;
|
|
BDRVQcow2State *s = bs->opaque;
|
|
int64_t offset;
|
|
uint64_t limit;
|
|
uint64_t bm_size = bdrv_dirty_bitmap_size(bitmap);
|
|
const char *bm_name = bdrv_dirty_bitmap_name(bitmap);
|
|
uint8_t *buf = NULL;
|
|
BdrvDirtyBitmapIter *dbi;
|
|
uint64_t *tb;
|
|
uint64_t tb_size =
|
|
size_to_clusters(s,
|
|
bdrv_dirty_bitmap_serialization_size(bitmap, 0, bm_size));
|
|
|
|
if (tb_size > BME_MAX_TABLE_SIZE ||
|
|
tb_size * s->cluster_size > BME_MAX_PHYS_SIZE)
|
|
{
|
|
error_setg(errp, "Bitmap '%s' is too big", bm_name);
|
|
return NULL;
|
|
}
|
|
|
|
tb = g_try_new0(uint64_t, tb_size);
|
|
if (tb == NULL) {
|
|
error_setg(errp, "No memory");
|
|
return NULL;
|
|
}
|
|
|
|
dbi = bdrv_dirty_iter_new(bitmap);
|
|
buf = g_malloc(s->cluster_size);
|
|
limit = bytes_covered_by_bitmap_cluster(s, bitmap);
|
|
assert(DIV_ROUND_UP(bm_size, limit) == tb_size);
|
|
|
|
while ((offset = bdrv_dirty_iter_next(dbi)) >= 0) {
|
|
uint64_t cluster = offset / limit;
|
|
uint64_t end, write_size;
|
|
int64_t off;
|
|
|
|
/*
|
|
* We found the first dirty offset, but want to write out the
|
|
* entire cluster of the bitmap that includes that offset,
|
|
* including any leading zero bits.
|
|
*/
|
|
offset = QEMU_ALIGN_DOWN(offset, limit);
|
|
end = MIN(bm_size, offset + limit);
|
|
write_size = bdrv_dirty_bitmap_serialization_size(bitmap, offset,
|
|
end - offset);
|
|
assert(write_size <= s->cluster_size);
|
|
|
|
off = qcow2_alloc_clusters(bs, s->cluster_size);
|
|
if (off < 0) {
|
|
error_setg_errno(errp, -off,
|
|
"Failed to allocate clusters for bitmap '%s'",
|
|
bm_name);
|
|
goto fail;
|
|
}
|
|
tb[cluster] = off;
|
|
|
|
bdrv_dirty_bitmap_serialize_part(bitmap, buf, offset, end - offset);
|
|
if (write_size < s->cluster_size) {
|
|
memset(buf + write_size, 0, s->cluster_size - write_size);
|
|
}
|
|
|
|
ret = qcow2_pre_write_overlap_check(bs, 0, off, s->cluster_size);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Qcow2 overlap check failed");
|
|
goto fail;
|
|
}
|
|
|
|
ret = bdrv_pwrite(bs->file, off, buf, s->cluster_size);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Failed to write bitmap '%s' to file",
|
|
bm_name);
|
|
goto fail;
|
|
}
|
|
|
|
if (end >= bm_size) {
|
|
break;
|
|
}
|
|
|
|
bdrv_set_dirty_iter(dbi, end);
|
|
}
|
|
|
|
*bitmap_table_size = tb_size;
|
|
g_free(buf);
|
|
bdrv_dirty_iter_free(dbi);
|
|
|
|
return tb;
|
|
|
|
fail:
|
|
clear_bitmap_table(bs, tb, tb_size);
|
|
g_free(buf);
|
|
bdrv_dirty_iter_free(dbi);
|
|
g_free(tb);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/* store_bitmap()
|
|
* Store bm->dirty_bitmap to qcow2.
|
|
* Set bm->table_offset and bm->table_size accordingly.
|
|
*/
|
|
static int store_bitmap(BlockDriverState *bs, Qcow2Bitmap *bm, Error **errp)
|
|
{
|
|
int ret;
|
|
uint64_t *tb;
|
|
int64_t tb_offset;
|
|
uint32_t tb_size;
|
|
BdrvDirtyBitmap *bitmap = bm->dirty_bitmap;
|
|
const char *bm_name;
|
|
|
|
assert(bitmap != NULL);
|
|
|
|
bm_name = bdrv_dirty_bitmap_name(bitmap);
|
|
|
|
tb = store_bitmap_data(bs, bitmap, &tb_size, errp);
|
|
if (tb == NULL) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
assert(tb_size <= BME_MAX_TABLE_SIZE);
|
|
tb_offset = qcow2_alloc_clusters(bs, tb_size * sizeof(tb[0]));
|
|
if (tb_offset < 0) {
|
|
error_setg_errno(errp, -tb_offset,
|
|
"Failed to allocate clusters for bitmap '%s'",
|
|
bm_name);
|
|
ret = tb_offset;
|
|
goto fail;
|
|
}
|
|
|
|
ret = qcow2_pre_write_overlap_check(bs, 0, tb_offset,
|
|
tb_size * sizeof(tb[0]));
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Qcow2 overlap check failed");
|
|
goto fail;
|
|
}
|
|
|
|
bitmap_table_to_be(tb, tb_size);
|
|
ret = bdrv_pwrite(bs->file, tb_offset, tb, tb_size * sizeof(tb[0]));
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Failed to write bitmap '%s' to file",
|
|
bm_name);
|
|
goto fail;
|
|
}
|
|
|
|
g_free(tb);
|
|
|
|
bm->table.offset = tb_offset;
|
|
bm->table.size = tb_size;
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
clear_bitmap_table(bs, tb, tb_size);
|
|
|
|
if (tb_offset > 0) {
|
|
qcow2_free_clusters(bs, tb_offset, tb_size * sizeof(tb[0]),
|
|
QCOW2_DISCARD_OTHER);
|
|
}
|
|
|
|
g_free(tb);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static Qcow2Bitmap *find_bitmap_by_name(Qcow2BitmapList *bm_list,
|
|
const char *name)
|
|
{
|
|
Qcow2Bitmap *bm;
|
|
|
|
QSIMPLEQ_FOREACH(bm, bm_list, entry) {
|
|
if (strcmp(name, bm->name) == 0) {
|
|
return bm;
|
|
}
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
void qcow2_remove_persistent_dirty_bitmap(BlockDriverState *bs,
|
|
const char *name,
|
|
Error **errp)
|
|
{
|
|
int ret;
|
|
BDRVQcow2State *s = bs->opaque;
|
|
Qcow2Bitmap *bm;
|
|
Qcow2BitmapList *bm_list;
|
|
|
|
if (s->nb_bitmaps == 0) {
|
|
/* Absence of the bitmap is not an error: see explanation above
|
|
* bdrv_remove_persistent_dirty_bitmap() definition. */
|
|
return;
|
|
}
|
|
|
|
bm_list = bitmap_list_load(bs, s->bitmap_directory_offset,
|
|
s->bitmap_directory_size, errp);
|
|
if (bm_list == NULL) {
|
|
return;
|
|
}
|
|
|
|
bm = find_bitmap_by_name(bm_list, name);
|
|
if (bm == NULL) {
|
|
goto fail;
|
|
}
|
|
|
|
QSIMPLEQ_REMOVE(bm_list, bm, Qcow2Bitmap, entry);
|
|
|
|
ret = update_ext_header_and_dir(bs, bm_list);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Failed to update bitmap extension");
|
|
goto fail;
|
|
}
|
|
|
|
free_bitmap_clusters(bs, &bm->table);
|
|
|
|
fail:
|
|
bitmap_free(bm);
|
|
bitmap_list_free(bm_list);
|
|
}
|
|
|
|
void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error **errp)
|
|
{
|
|
BdrvDirtyBitmap *bitmap;
|
|
BDRVQcow2State *s = bs->opaque;
|
|
uint32_t new_nb_bitmaps = s->nb_bitmaps;
|
|
uint64_t new_dir_size = s->bitmap_directory_size;
|
|
int ret;
|
|
Qcow2BitmapList *bm_list;
|
|
Qcow2Bitmap *bm;
|
|
Qcow2BitmapTableList drop_tables;
|
|
Qcow2BitmapTable *tb, *tb_next;
|
|
|
|
if (!bdrv_has_changed_persistent_bitmaps(bs)) {
|
|
/* nothing to do */
|
|
return;
|
|
}
|
|
|
|
if (!can_write(bs)) {
|
|
error_setg(errp, "No write access");
|
|
return;
|
|
}
|
|
|
|
QSIMPLEQ_INIT(&drop_tables);
|
|
|
|
if (s->nb_bitmaps == 0) {
|
|
bm_list = bitmap_list_new();
|
|
} else {
|
|
bm_list = bitmap_list_load(bs, s->bitmap_directory_offset,
|
|
s->bitmap_directory_size, errp);
|
|
if (bm_list == NULL) {
|
|
return;
|
|
}
|
|
}
|
|
|
|
/* check constraints and names */
|
|
for (bitmap = bdrv_dirty_bitmap_next(bs, NULL); bitmap != NULL;
|
|
bitmap = bdrv_dirty_bitmap_next(bs, bitmap))
|
|
{
|
|
const char *name = bdrv_dirty_bitmap_name(bitmap);
|
|
uint32_t granularity = bdrv_dirty_bitmap_granularity(bitmap);
|
|
Qcow2Bitmap *bm;
|
|
|
|
if (!bdrv_dirty_bitmap_get_persistance(bitmap) ||
|
|
bdrv_dirty_bitmap_readonly(bitmap))
|
|
{
|
|
continue;
|
|
}
|
|
|
|
if (check_constraints_on_bitmap(bs, name, granularity, errp) < 0) {
|
|
error_prepend(errp, "Bitmap '%s' doesn't satisfy the constraints: ",
|
|
name);
|
|
goto fail;
|
|
}
|
|
|
|
bm = find_bitmap_by_name(bm_list, name);
|
|
if (bm == NULL) {
|
|
if (++new_nb_bitmaps > QCOW2_MAX_BITMAPS) {
|
|
error_setg(errp, "Too many persistent bitmaps");
|
|
goto fail;
|
|
}
|
|
|
|
new_dir_size += calc_dir_entry_size(strlen(name), 0);
|
|
if (new_dir_size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) {
|
|
error_setg(errp, "Bitmap directory is too large");
|
|
goto fail;
|
|
}
|
|
|
|
bm = g_new0(Qcow2Bitmap, 1);
|
|
bm->name = g_strdup(name);
|
|
QSIMPLEQ_INSERT_TAIL(bm_list, bm, entry);
|
|
} else {
|
|
if (!(bm->flags & BME_FLAG_IN_USE)) {
|
|
error_setg(errp, "Bitmap '%s' already exists in the image",
|
|
name);
|
|
goto fail;
|
|
}
|
|
tb = g_memdup(&bm->table, sizeof(bm->table));
|
|
bm->table.offset = 0;
|
|
bm->table.size = 0;
|
|
QSIMPLEQ_INSERT_TAIL(&drop_tables, tb, entry);
|
|
}
|
|
bm->flags = bdrv_dirty_bitmap_enabled(bitmap) ? BME_FLAG_AUTO : 0;
|
|
bm->granularity_bits = ctz32(bdrv_dirty_bitmap_granularity(bitmap));
|
|
bm->dirty_bitmap = bitmap;
|
|
}
|
|
|
|
/* allocate clusters and store bitmaps */
|
|
QSIMPLEQ_FOREACH(bm, bm_list, entry) {
|
|
if (bm->dirty_bitmap == NULL) {
|
|
continue;
|
|
}
|
|
|
|
ret = store_bitmap(bs, bm, errp);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
}
|
|
|
|
ret = update_ext_header_and_dir(bs, bm_list);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Failed to update bitmap extension");
|
|
goto fail;
|
|
}
|
|
|
|
/* Bitmap directory was successfully updated, so, old data can be dropped.
|
|
* TODO it is better to reuse these clusters */
|
|
QSIMPLEQ_FOREACH_SAFE(tb, &drop_tables, entry, tb_next) {
|
|
free_bitmap_clusters(bs, tb);
|
|
g_free(tb);
|
|
}
|
|
|
|
bitmap_list_free(bm_list);
|
|
return;
|
|
|
|
fail:
|
|
QSIMPLEQ_FOREACH(bm, bm_list, entry) {
|
|
if (bm->dirty_bitmap == NULL || bm->table.offset == 0) {
|
|
continue;
|
|
}
|
|
|
|
free_bitmap_clusters(bs, &bm->table);
|
|
}
|
|
|
|
QSIMPLEQ_FOREACH_SAFE(tb, &drop_tables, entry, tb_next) {
|
|
g_free(tb);
|
|
}
|
|
|
|
bitmap_list_free(bm_list);
|
|
}
|
|
|
|
int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp)
|
|
{
|
|
BdrvDirtyBitmap *bitmap;
|
|
Error *local_err = NULL;
|
|
|
|
qcow2_store_persistent_dirty_bitmaps(bs, &local_err);
|
|
if (local_err != NULL) {
|
|
error_propagate(errp, local_err);
|
|
return -EINVAL;
|
|
}
|
|
|
|
for (bitmap = bdrv_dirty_bitmap_next(bs, NULL); bitmap != NULL;
|
|
bitmap = bdrv_dirty_bitmap_next(bs, bitmap))
|
|
{
|
|
if (bdrv_dirty_bitmap_get_persistance(bitmap)) {
|
|
bdrv_dirty_bitmap_set_readonly(bitmap, true);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
bool qcow2_can_store_new_dirty_bitmap(BlockDriverState *bs,
|
|
const char *name,
|
|
uint32_t granularity,
|
|
Error **errp)
|
|
{
|
|
BDRVQcow2State *s = bs->opaque;
|
|
bool found;
|
|
Qcow2BitmapList *bm_list;
|
|
|
|
if (s->qcow_version < 3) {
|
|
/* Without autoclear_features, we would always have to assume
|
|
* that a program without persistent dirty bitmap support has
|
|
* accessed this qcow2 file when opening it, and would thus
|
|
* have to drop all dirty bitmaps (defeating their purpose).
|
|
*/
|
|
error_setg(errp, "Cannot store dirty bitmaps in qcow2 v2 files");
|
|
goto fail;
|
|
}
|
|
|
|
if (check_constraints_on_bitmap(bs, name, granularity, errp) != 0) {
|
|
goto fail;
|
|
}
|
|
|
|
if (s->nb_bitmaps == 0) {
|
|
return true;
|
|
}
|
|
|
|
if (s->nb_bitmaps >= QCOW2_MAX_BITMAPS) {
|
|
error_setg(errp,
|
|
"Maximum number of persistent bitmaps is already reached");
|
|
goto fail;
|
|
}
|
|
|
|
if (s->bitmap_directory_size + calc_dir_entry_size(strlen(name), 0) >
|
|
QCOW2_MAX_BITMAP_DIRECTORY_SIZE)
|
|
{
|
|
error_setg(errp, "Not enough space in the bitmap directory");
|
|
goto fail;
|
|
}
|
|
|
|
bm_list = bitmap_list_load(bs, s->bitmap_directory_offset,
|
|
s->bitmap_directory_size, errp);
|
|
if (bm_list == NULL) {
|
|
goto fail;
|
|
}
|
|
|
|
found = find_bitmap_by_name(bm_list, name);
|
|
bitmap_list_free(bm_list);
|
|
if (found) {
|
|
error_setg(errp, "Bitmap with the same name is already stored");
|
|
goto fail;
|
|
}
|
|
|
|
return true;
|
|
|
|
fail:
|
|
error_prepend(errp, "Can't make bitmap '%s' persistent in '%s': ",
|
|
name, bdrv_get_device_or_node_name(bs));
|
|
return false;
|
|
}
|