#define VMDK3_MAGIC (('C' << 24) | ('O' << 16) | ('W' << 8) | 'D')
#define VMDK4_MAGIC (('K' << 24) | ('D' << 16) | ('M' << 8) | 'V')
#define VMDK4_COMPRESSION_DEFLATE 1
+#define VMDK4_FLAG_NL_DETECT (1 << 0)
#define VMDK4_FLAG_RGD (1 << 1)
+/* Zeroed-grain enable bit */
+#define VMDK4_FLAG_ZERO_GRAIN (1 << 2)
#define VMDK4_FLAG_COMPRESS (1 << 16)
#define VMDK4_FLAG_MARKER (1 << 17)
#define VMDK4_GD_AT_END 0xffffffffffffffffULL
+#define VMDK_GTE_ZEROED 0x1
+
+/* VMDK internal error codes */
+#define VMDK_OK 0
+#define VMDK_ERROR (-1)
+/* Cluster not allocated */
+#define VMDK_UNALLOC (-2)
+#define VMDK_ZEROED (-3)
+
+#define BLOCK_OPT_ZEROED_GRAIN "zeroed_grain"
+
typedef struct {
uint32_t version;
uint32_t flags;
uint32_t cylinders;
uint32_t heads;
uint32_t sectors_per_track;
-} VMDK3Header;
+} QEMU_PACKED VMDK3Header;
typedef struct {
uint32_t version;
bool flat;
bool compressed;
bool has_marker;
+ bool has_zero_grain;
+ int version;
int64_t sectors;
int64_t end_sector;
int64_t flat_start_offset;
unsigned int l2_index;
unsigned int l2_offset;
int valid;
+ uint32_t *l2_cache_entry;
} VmdkMetaData;
typedef struct VmdkGrainMarker {
uint64_t lba;
uint32_t size;
uint8_t data[0];
-} VmdkGrainMarker;
+} QEMU_PACKED VmdkGrainMarker;
enum {
MARKER_END_OF_STREAM = 0,
if (ret < 0) {
return ret;
}
- if (header.capacity == 0 && header.desc_offset) {
- return vmdk_open_desc_file(bs, flags, header.desc_offset << 9);
+ if (header.capacity == 0) {
+ int64_t desc_offset = le64_to_cpu(header.desc_offset);
+ if (desc_offset) {
+ return vmdk_open_desc_file(bs, flags, desc_offset << 9);
+ }
}
if (le64_to_cpu(header.gd_offset) == VMDK4_GD_AT_END) {
header = footer.header;
}
+ if (le32_to_cpu(header.version) >= 3) {
+ char buf[64];
+ snprintf(buf, sizeof(buf), "VMDK version %d",
+ le32_to_cpu(header.version));
+ qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
+ bs->device_name, "vmdk", buf);
+ return -ENOTSUP;
+ }
+
l1_entry_sectors = le32_to_cpu(header.num_gtes_per_gte)
* le64_to_cpu(header.granularity);
if (l1_entry_sectors == 0) {
extent->compressed =
le16_to_cpu(header.compressAlgorithm) == VMDK4_COMPRESSION_DEFLATE;
extent->has_marker = le32_to_cpu(header.flags) & VMDK4_FLAG_MARKER;
+ extent->version = le32_to_cpu(header.version);
+ extent->has_zero_grain = le32_to_cpu(header.flags) & VMDK4_FLAG_ZERO_GRAIN;
ret = vmdk_init_tables(bs, extent);
if (ret) {
/* free extent allocated by vmdk_add_extent */
opt_pos = strstr(desc, opt_name);
if (!opt_pos) {
- return -1;
+ return VMDK_ERROR;
}
/* Skip "=\"" following opt_name */
opt_pos += strlen(opt_name) + 2;
if (opt_pos >= end) {
- return -1;
+ return VMDK_ERROR;
}
opt_end = opt_pos;
while (opt_end < end && *opt_end != '"') {
opt_end++;
}
if (opt_end == end || buf_size < opt_end - opt_pos + 1) {
- return -1;
+ return VMDK_ERROR;
}
pstrcpy(buf, opt_end - opt_pos + 1, opt_pos);
- return 0;
+ return VMDK_OK;
}
/* Open an extent file and append to bs array */
path_combine(extent_path, sizeof(extent_path),
desc_file_path, fname);
- ret = bdrv_file_open(&extent_file, extent_path, bs->open_flags);
+ ret = bdrv_file_open(&extent_file, extent_path, NULL, bs->open_flags);
if (ret) {
return ret;
}
int64_t desc_offset)
{
int ret;
- char buf[2048];
+ char *buf = NULL;
char ct[128];
BDRVVmdkState *s = bs->opaque;
+ int64_t size;
+
+ size = bdrv_getlength(bs->file);
+ if (size < 0) {
+ return -EINVAL;
+ }
- ret = bdrv_pread(bs->file, desc_offset, buf, sizeof(buf));
+ size = MIN(size, 1 << 20); /* avoid unbounded allocation */
+ buf = g_malloc0(size + 1);
+
+ ret = bdrv_pread(bs->file, desc_offset, buf, size);
if (ret < 0) {
- return ret;
+ goto exit;
}
- buf[2047] = '\0';
if (vmdk_parse_description(buf, "createType", ct, sizeof(ct))) {
- return -EMEDIUMTYPE;
+ ret = -EMEDIUMTYPE;
+ goto exit;
}
if (strcmp(ct, "monolithicFlat") &&
strcmp(ct, "twoGbMaxExtentSparse") &&
strcmp(ct, "twoGbMaxExtentFlat")) {
fprintf(stderr,
"VMDK: Not supported image type \"%s\""".\n", ct);
- return -ENOTSUP;
+ ret = -ENOTSUP;
+ goto exit;
}
s->desc_offset = 0;
- return vmdk_parse_extents(buf, bs, bs->file->filename);
+ ret = vmdk_parse_extents(buf, bs, bs->file->filename);
+exit:
+ g_free(buf);
+ return ret;
}
static int vmdk_open(BlockDriverState *bs, QDict *options, int flags)
int ret;
if (!vmdk_is_cid_valid(bs)) {
- return -1;
+ return VMDK_ERROR;
}
/* floor offset to cluster */
ret = bdrv_read(bs->backing_hd, offset >> 9, whole_grain,
extent->cluster_sectors);
if (ret < 0) {
- return -1;
+ return VMDK_ERROR;
}
/* Write grain only into the active image */
ret = bdrv_write(extent->file, cluster_offset, whole_grain,
extent->cluster_sectors);
if (ret < 0) {
- return -1;
+ return VMDK_ERROR;
}
}
- return 0;
+ return VMDK_OK;
}
static int vmdk_L2update(VmdkExtent *extent, VmdkMetaData *m_data)
{
+ uint32_t offset;
+ QEMU_BUILD_BUG_ON(sizeof(offset) != sizeof(m_data->offset));
+ offset = cpu_to_le32(m_data->offset);
/* update L2 table */
if (bdrv_pwrite_sync(
extent->file,
((int64_t)m_data->l2_offset * 512)
+ (m_data->l2_index * sizeof(m_data->offset)),
- &(m_data->offset),
- sizeof(m_data->offset)
- ) < 0) {
- return -1;
+ &offset, sizeof(offset)) < 0) {
+ return VMDK_ERROR;
}
/* update backup L2 table */
if (extent->l1_backup_table_offset != 0) {
extent->file,
((int64_t)m_data->l2_offset * 512)
+ (m_data->l2_index * sizeof(m_data->offset)),
- &(m_data->offset), sizeof(m_data->offset)
- ) < 0) {
- return -1;
+ &offset, sizeof(offset)) < 0) {
+ return VMDK_ERROR;
}
}
+ if (m_data->l2_cache_entry) {
+ *m_data->l2_cache_entry = offset;
+ }
- return 0;
+ return VMDK_OK;
}
static int get_cluster_offset(BlockDriverState *bs,
{
unsigned int l1_index, l2_offset, l2_index;
int min_index, i, j;
- uint32_t min_count, *l2_table, tmp = 0;
+ uint32_t min_count, *l2_table;
+ bool zeroed = false;
if (m_data) {
m_data->valid = 0;
}
if (extent->flat) {
*cluster_offset = extent->flat_start_offset;
- return 0;
+ return VMDK_OK;
}
offset -= (extent->end_sector - extent->sectors) * SECTOR_SIZE;
l1_index = (offset >> 9) / extent->l1_entry_sectors;
if (l1_index >= extent->l1_size) {
- return -1;
+ return VMDK_ERROR;
}
l2_offset = extent->l1_table[l1_index];
if (!l2_offset) {
- return -1;
+ return VMDK_UNALLOC;
}
for (i = 0; i < L2_CACHE_SIZE; i++) {
if (l2_offset == extent->l2_cache_offsets[i]) {
l2_table,
extent->l2_size * sizeof(uint32_t)
) != extent->l2_size * sizeof(uint32_t)) {
- return -1;
+ return VMDK_ERROR;
}
extent->l2_cache_offsets[min_index] = l2_offset;
l2_index = ((offset >> 9) / extent->cluster_sectors) % extent->l2_size;
*cluster_offset = le32_to_cpu(l2_table[l2_index]);
- if (!*cluster_offset) {
+ if (m_data) {
+ m_data->valid = 1;
+ m_data->l1_index = l1_index;
+ m_data->l2_index = l2_index;
+ m_data->offset = *cluster_offset;
+ m_data->l2_offset = l2_offset;
+ m_data->l2_cache_entry = &l2_table[l2_index];
+ }
+ if (extent->has_zero_grain && *cluster_offset == VMDK_GTE_ZEROED) {
+ zeroed = true;
+ }
+
+ if (!*cluster_offset || zeroed) {
if (!allocate) {
- return -1;
+ return zeroed ? VMDK_ZEROED : VMDK_UNALLOC;
}
/* Avoid the L2 tables update for the images that have snapshots. */
}
*cluster_offset >>= 9;
- tmp = cpu_to_le32(*cluster_offset);
- l2_table[l2_index] = tmp;
+ l2_table[l2_index] = cpu_to_le32(*cluster_offset);
/* First of all we write grain itself, to avoid race condition
* that may to corrupt the image.
*/
if (get_whole_cluster(
bs, extent, *cluster_offset, offset, allocate) == -1) {
- return -1;
+ return VMDK_ERROR;
}
if (m_data) {
- m_data->offset = tmp;
- m_data->l1_index = l1_index;
- m_data->l2_index = l2_index;
- m_data->l2_offset = l2_offset;
- m_data->valid = 1;
+ m_data->offset = *cluster_offset;
}
}
*cluster_offset <<= 9;
- return 0;
+ return VMDK_OK;
}
static VmdkExtent *find_extent(BDRVVmdkState *s,
ret = get_cluster_offset(bs, extent, NULL,
sector_num * 512, 0, &offset);
qemu_co_mutex_unlock(&s->lock);
- /* get_cluster_offset returning 0 means success */
- ret = !ret;
+
+ ret = (ret == VMDK_OK || ret == VMDK_ZEROED);
index_in_cluster = sector_num % extent->cluster_sectors;
n = extent->cluster_sectors - index_in_cluster;
if (n > nb_sectors) {
n = nb_sectors;
}
- if (ret) {
+ if (ret != VMDK_OK) {
/* if not allocated, try to read from parent image, if exist */
- if (bs->backing_hd) {
+ if (bs->backing_hd && ret != VMDK_ZEROED) {
if (!vmdk_is_cid_valid(bs)) {
return -EINVAL;
}
return ret;
}
+/**
+ * vmdk_write:
+ * @zeroed: buf is ignored (data is zero), use zeroed_grain GTE feature
+ * if possible, otherwise return -ENOTSUP.
+ * @zero_dry_run: used for zeroed == true only, don't update L2 table, just try
+ * with each cluster. By dry run we can find if the zero write
+ * is possible without modifying image data.
+ *
+ * Returns: error code with 0 for success.
+ */
static int vmdk_write(BlockDriverState *bs, int64_t sector_num,
- const uint8_t *buf, int nb_sectors)
+ const uint8_t *buf, int nb_sectors,
+ bool zeroed, bool zero_dry_run)
{
BDRVVmdkState *s = bs->opaque;
VmdkExtent *extent = NULL;
sector_num << 9, !extent->compressed,
&cluster_offset);
if (extent->compressed) {
- if (ret == 0) {
+ if (ret == VMDK_OK) {
/* Refuse write to allocated cluster for streamOptimized */
fprintf(stderr,
"VMDK: can't write to allocated cluster"
&cluster_offset);
}
}
- if (ret) {
+ if (ret == VMDK_ERROR) {
return -EINVAL;
}
extent_begin_sector = extent->end_sector - extent->sectors;
if (n > nb_sectors) {
n = nb_sectors;
}
-
- ret = vmdk_write_extent(extent,
- cluster_offset, index_in_cluster * 512,
- buf, n, sector_num);
- if (ret) {
- return ret;
- }
- if (m_data.valid) {
- /* update L2 tables */
- if (vmdk_L2update(extent, &m_data) == -1) {
- return -EIO;
+ if (zeroed) {
+ /* Do zeroed write, buf is ignored */
+ if (extent->has_zero_grain &&
+ index_in_cluster == 0 &&
+ n >= extent->cluster_sectors) {
+ n = extent->cluster_sectors;
+ if (!zero_dry_run) {
+ m_data.offset = VMDK_GTE_ZEROED;
+ /* update L2 tables */
+ if (vmdk_L2update(extent, &m_data) != VMDK_OK) {
+ return -EIO;
+ }
+ }
+ } else {
+ return -ENOTSUP;
+ }
+ } else {
+ ret = vmdk_write_extent(extent,
+ cluster_offset, index_in_cluster * 512,
+ buf, n, sector_num);
+ if (ret) {
+ return ret;
+ }
+ if (m_data.valid) {
+ /* update L2 tables */
+ if (vmdk_L2update(extent, &m_data) != VMDK_OK) {
+ return -EIO;
+ }
}
}
nb_sectors -= n;
int ret;
BDRVVmdkState *s = bs->opaque;
qemu_co_mutex_lock(&s->lock);
- ret = vmdk_write(bs, sector_num, buf, nb_sectors);
+ ret = vmdk_write(bs, sector_num, buf, nb_sectors, false, false);
+ qemu_co_mutex_unlock(&s->lock);
+ return ret;
+}
+
+static int coroutine_fn vmdk_co_write_zeroes(BlockDriverState *bs,
+ int64_t sector_num,
+ int nb_sectors)
+{
+ int ret;
+ BDRVVmdkState *s = bs->opaque;
+ qemu_co_mutex_lock(&s->lock);
+ /* write zeroes could fail if sectors not aligned to cluster, test it with
+ * dry_run == true before really updating image */
+ ret = vmdk_write(bs, sector_num, NULL, nb_sectors, true, true);
+ if (!ret) {
+ ret = vmdk_write(bs, sector_num, NULL, nb_sectors, true, false);
+ }
qemu_co_mutex_unlock(&s->lock);
return ret;
}
static int vmdk_create_extent(const char *filename, int64_t filesize,
- bool flat, bool compress)
+ bool flat, bool compress, bool zeroed_grain)
{
int ret, i;
int fd = 0;
}
magic = cpu_to_be32(VMDK4_MAGIC);
memset(&header, 0, sizeof(header));
- header.version = 1;
- header.flags =
- 3 | (compress ? VMDK4_FLAG_COMPRESS | VMDK4_FLAG_MARKER : 0);
+ header.version = zeroed_grain ? 2 : 1;
+ header.flags = VMDK4_FLAG_RGD | VMDK4_FLAG_NL_DETECT
+ | (compress ? VMDK4_FLAG_COMPRESS | VMDK4_FLAG_MARKER : 0)
+ | (zeroed_grain ? VMDK4_FLAG_ZERO_GRAIN : 0);
header.compressAlgorithm = compress ? VMDK4_COMPRESSION_DEFLATE : 0;
header.capacity = filesize / 512;
header.granularity = 128;
if (filename == NULL || !strlen(filename)) {
fprintf(stderr, "Vmdk: no filename provided.\n");
- return -1;
+ return VMDK_ERROR;
}
p = strrchr(filename, '/');
if (p == NULL) {
if (p != NULL) {
p++;
if (p - filename >= buf_len) {
- return -1;
+ return VMDK_ERROR;
}
pstrcpy(path, p - filename + 1, filename);
} else {
postfix[0] = '\0';
} else {
if (q - p >= buf_len) {
- return -1;
+ return VMDK_ERROR;
}
pstrcpy(prefix, q - p + 1, p);
pstrcpy(postfix, buf_len, q);
}
- return 0;
-}
-
-static int relative_path(char *dest, int dest_size,
- const char *base, const char *target)
-{
- int i = 0;
- int n = 0;
- const char *p, *q;
-#ifdef _WIN32
- const char *sep = "\\";
-#else
- const char *sep = "/";
-#endif
-
- if (!(dest && base && target)) {
- return -1;
- }
- if (path_is_absolute(target)) {
- pstrcpy(dest, dest_size, target);
- return 0;
- }
- while (base[i] == target[i]) {
- i++;
- }
- p = &base[i];
- q = &target[i];
- while (*p) {
- if (*p == *sep) {
- n++;
- }
- p++;
- }
- dest[0] = '\0';
- for (; n; n--) {
- pstrcat(dest, dest_size, "..");
- pstrcat(dest, dest_size, sep);
- }
- pstrcat(dest, dest_size, q);
- return 0;
+ return VMDK_OK;
}
static int vmdk_create(const char *filename, QEMUOptionParameter *options)
char parent_desc_line[BUF_SIZE] = "";
uint32_t parent_cid = 0xffffffff;
uint32_t number_heads = 16;
+ bool zeroed_grain = false;
const char desc_template[] =
"# Disk DescriptorFile\n"
"version=1\n"
flags |= options->value.n ? BLOCK_FLAG_COMPAT6 : 0;
} else if (!strcmp(options->name, BLOCK_OPT_SUBFMT)) {
fmt = options->value.s;
+ } else if (!strcmp(options->name, BLOCK_OPT_ZEROED_GRAIN)) {
+ zeroed_grain |= options->value.n;
}
options++;
}
return -ENOTSUP;
}
if (backing_file) {
- char parent_filename[PATH_MAX];
BlockDriverState *bs = bdrv_new("");
ret = bdrv_open(bs, backing_file, NULL, 0, NULL);
if (ret != 0) {
}
parent_cid = vmdk_read_cid(bs, 0);
bdrv_delete(bs);
- relative_path(parent_filename, sizeof(parent_filename),
- filename, backing_file);
snprintf(parent_desc_line, sizeof(parent_desc_line),
- "parentFileNameHint=\"%s\"", parent_filename);
+ "parentFileNameHint=\"%s\"", backing_file);
}
/* Create extents */
snprintf(ext_filename, sizeof(ext_filename), "%s%s",
path, desc_filename);
- if (vmdk_create_extent(ext_filename, size, flat, compress)) {
+ if (vmdk_create_extent(ext_filename, size,
+ flat, compress, zeroed_grain)) {
return -EINVAL;
}
filesize -= size;
return ret;
}
+static int vmdk_has_zero_init(BlockDriverState *bs)
+{
+ int i;
+ BDRVVmdkState *s = bs->opaque;
+
+ /* If has a flat extent and its underlying storage doesn't have zero init,
+ * return 0. */
+ for (i = 0; i < s->num_extents; i++) {
+ if (s->extents[i].flat) {
+ if (!bdrv_has_zero_init(s->extents[i].file)) {
+ return 0;
+ }
+ }
+ }
+ return 1;
+}
+
static QEMUOptionParameter vmdk_create_options[] = {
{
.name = BLOCK_OPT_SIZE,
"VMDK flat extent format, can be one of "
"{monolithicSparse (default) | monolithicFlat | twoGbMaxExtentSparse | twoGbMaxExtentFlat | streamOptimized} "
},
+ {
+ .name = BLOCK_OPT_ZEROED_GRAIN,
+ .type = OPT_FLAG,
+ .help = "Enable efficient zero writes using the zeroed-grain GTE feature"
+ },
{ NULL }
};
static BlockDriver bdrv_vmdk = {
- .format_name = "vmdk",
- .instance_size = sizeof(BDRVVmdkState),
- .bdrv_probe = vmdk_probe,
- .bdrv_open = vmdk_open,
- .bdrv_reopen_prepare = vmdk_reopen_prepare,
- .bdrv_read = vmdk_co_read,
- .bdrv_write = vmdk_co_write,
- .bdrv_close = vmdk_close,
- .bdrv_create = vmdk_create,
- .bdrv_co_flush_to_disk = vmdk_co_flush,
- .bdrv_co_is_allocated = vmdk_co_is_allocated,
- .bdrv_get_allocated_file_size = vmdk_get_allocated_file_size,
-
- .create_options = vmdk_create_options,
+ .format_name = "vmdk",
+ .instance_size = sizeof(BDRVVmdkState),
+ .bdrv_probe = vmdk_probe,
+ .bdrv_open = vmdk_open,
+ .bdrv_reopen_prepare = vmdk_reopen_prepare,
+ .bdrv_read = vmdk_co_read,
+ .bdrv_write = vmdk_co_write,
+ .bdrv_co_write_zeroes = vmdk_co_write_zeroes,
+ .bdrv_close = vmdk_close,
+ .bdrv_create = vmdk_create,
+ .bdrv_co_flush_to_disk = vmdk_co_flush,
+ .bdrv_co_is_allocated = vmdk_co_is_allocated,
+ .bdrv_get_allocated_file_size = vmdk_get_allocated_file_size,
+ .bdrv_has_zero_init = vmdk_has_zero_init,
+
+ .create_options = vmdk_create_options,
};
static void bdrv_vmdk_init(void)
projects / qemu.git / blobdiff