aboutsummaryrefslogtreecommitdiff
path: root/block/qcow2.c
diff options
context:
space:
mode:
Diffstat (limited to 'block/qcow2.c')
-rw-r--r--block/qcow2.c490
1 files changed, 245 insertions, 245 deletions
diff --git a/block/qcow2.c b/block/qcow2.c
index 21ed6f8753..3dbe4b8889 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -52,7 +52,7 @@ typedef struct {
#define QCOW_EXT_MAGIC_END 0
#define QCOW_EXT_MAGIC_BACKING_FORMAT 0xE2792ACA
-static int qcow_create(const char *filename, QEMUOptionParameter *options);
+static BlockDriver bdrv_qcow2;
static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename)
{
@@ -830,6 +830,250 @@ static int preallocate(BlockDriverState *bs)
return 0;
}
+static int qcow_create2(const char *filename, int64_t total_size,
+ const char *backing_file, const char *backing_format,
+ int flags, size_t cluster_size, int prealloc)
+{
+
+ int fd, header_size, backing_filename_len, l1_size, i, shift, l2_bits;
+ int ref_clusters, reftable_clusters, backing_format_len = 0;
+ int rounded_ext_bf_len = 0;
+ QCowHeader header;
+ uint64_t tmp, offset;
+ uint64_t old_ref_clusters;
+ QCowCreateState s1, *s = &s1;
+ QCowExtension ext_bf = {0, 0};
+ int ret;
+
+ memset(s, 0, sizeof(*s));
+
+ fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644);
+ if (fd < 0)
+ return -errno;
+ memset(&header, 0, sizeof(header));
+ header.magic = cpu_to_be32(QCOW_MAGIC);
+ header.version = cpu_to_be32(QCOW_VERSION);
+ header.size = cpu_to_be64(total_size * 512);
+ header_size = sizeof(header);
+ backing_filename_len = 0;
+ if (backing_file) {
+ if (backing_format) {
+ ext_bf.magic = QCOW_EXT_MAGIC_BACKING_FORMAT;
+ backing_format_len = strlen(backing_format);
+ ext_bf.len = backing_format_len;
+ rounded_ext_bf_len = (sizeof(ext_bf) + ext_bf.len + 7) & ~7;
+ header_size += rounded_ext_bf_len;
+ }
+ header.backing_file_offset = cpu_to_be64(header_size);
+ backing_filename_len = strlen(backing_file);
+ header.backing_file_size = cpu_to_be32(backing_filename_len);
+ header_size += backing_filename_len;
+ }
+
+ /* Cluster size */
+ s->cluster_bits = get_bits_from_size(cluster_size);
+ if (s->cluster_bits < MIN_CLUSTER_BITS ||
+ s->cluster_bits > MAX_CLUSTER_BITS)
+ {
+ fprintf(stderr, "Cluster size must be a power of two between "
+ "%d and %dk\n",
+ 1 << MIN_CLUSTER_BITS,
+ 1 << (MAX_CLUSTER_BITS - 10));
+ return -EINVAL;
+ }
+ s->cluster_size = 1 << s->cluster_bits;
+
+ header.cluster_bits = cpu_to_be32(s->cluster_bits);
+ header_size = (header_size + 7) & ~7;
+ if (flags & BLOCK_FLAG_ENCRYPT) {
+ header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES);
+ } else {
+ header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE);
+ }
+ l2_bits = s->cluster_bits - 3;
+ shift = s->cluster_bits + l2_bits;
+ l1_size = (((total_size * 512) + (1LL << shift) - 1) >> shift);
+ offset = align_offset(header_size, s->cluster_size);
+ s->l1_table_offset = offset;
+ header.l1_table_offset = cpu_to_be64(s->l1_table_offset);
+ header.l1_size = cpu_to_be32(l1_size);
+ offset += align_offset(l1_size * sizeof(uint64_t), s->cluster_size);
+
+ /* count how many refcount blocks needed */
+
+#define NUM_CLUSTERS(bytes) \
+ (((bytes) + (s->cluster_size) - 1) / (s->cluster_size))
+
+ ref_clusters = NUM_CLUSTERS(NUM_CLUSTERS(offset) * sizeof(uint16_t));
+
+ do {
+ uint64_t image_clusters;
+ old_ref_clusters = ref_clusters;
+
+ /* Number of clusters used for the refcount table */
+ reftable_clusters = NUM_CLUSTERS(ref_clusters * sizeof(uint64_t));
+
+ /* Number of clusters that the whole image will have */
+ image_clusters = NUM_CLUSTERS(offset) + ref_clusters
+ + reftable_clusters;
+
+ /* Number of refcount blocks needed for the image */
+ ref_clusters = NUM_CLUSTERS(image_clusters * sizeof(uint16_t));
+
+ } while (ref_clusters != old_ref_clusters);
+
+ s->refcount_table = qemu_mallocz(reftable_clusters * s->cluster_size);
+
+ s->refcount_table_offset = offset;
+ header.refcount_table_offset = cpu_to_be64(offset);
+ header.refcount_table_clusters = cpu_to_be32(reftable_clusters);
+ offset += (reftable_clusters * s->cluster_size);
+ s->refcount_block_offset = offset;
+
+ for (i=0; i < ref_clusters; i++) {
+ s->refcount_table[i] = cpu_to_be64(offset);
+ offset += s->cluster_size;
+ }
+
+ s->refcount_block = qemu_mallocz(ref_clusters * s->cluster_size);
+
+ /* update refcounts */
+ qcow2_create_refcount_update(s, 0, header_size);
+ qcow2_create_refcount_update(s, s->l1_table_offset,
+ l1_size * sizeof(uint64_t));
+ qcow2_create_refcount_update(s, s->refcount_table_offset,
+ reftable_clusters * s->cluster_size);
+ qcow2_create_refcount_update(s, s->refcount_block_offset,
+ ref_clusters * s->cluster_size);
+
+ /* write all the data */
+ ret = qemu_write_full(fd, &header, sizeof(header));
+ if (ret != sizeof(header)) {
+ ret = -errno;
+ goto exit;
+ }
+ if (backing_file) {
+ if (backing_format_len) {
+ char zero[16];
+ int padding = rounded_ext_bf_len - (ext_bf.len + sizeof(ext_bf));
+
+ memset(zero, 0, sizeof(zero));
+ cpu_to_be32s(&ext_bf.magic);
+ cpu_to_be32s(&ext_bf.len);
+ ret = qemu_write_full(fd, &ext_bf, sizeof(ext_bf));
+ if (ret != sizeof(ext_bf)) {
+ ret = -errno;
+ goto exit;
+ }
+ ret = qemu_write_full(fd, backing_format, backing_format_len);
+ if (ret != backing_format_len) {
+ ret = -errno;
+ goto exit;
+ }
+ if (padding > 0) {
+ ret = qemu_write_full(fd, zero, padding);
+ if (ret != padding) {
+ ret = -errno;
+ goto exit;
+ }
+ }
+ }
+ ret = qemu_write_full(fd, backing_file, backing_filename_len);
+ if (ret != backing_filename_len) {
+ ret = -errno;
+ goto exit;
+ }
+ }
+ lseek(fd, s->l1_table_offset, SEEK_SET);
+ tmp = 0;
+ for(i = 0;i < l1_size; i++) {
+ ret = qemu_write_full(fd, &tmp, sizeof(tmp));
+ if (ret != sizeof(tmp)) {
+ ret = -errno;
+ goto exit;
+ }
+ }
+ lseek(fd, s->refcount_table_offset, SEEK_SET);
+ ret = qemu_write_full(fd, s->refcount_table,
+ reftable_clusters * s->cluster_size);
+ if (ret != reftable_clusters * s->cluster_size) {
+ ret = -errno;
+ goto exit;
+ }
+
+ lseek(fd, s->refcount_block_offset, SEEK_SET);
+ ret = qemu_write_full(fd, s->refcount_block,
+ ref_clusters * s->cluster_size);
+ if (ret != ref_clusters * s->cluster_size) {
+ ret = -errno;
+ goto exit;
+ }
+
+ ret = 0;
+exit:
+ qemu_free(s->refcount_table);
+ qemu_free(s->refcount_block);
+ close(fd);
+
+ /* Preallocate metadata */
+ if (ret == 0 && prealloc) {
+ BlockDriverState *bs;
+ bs = bdrv_new("");
+ bdrv_open(bs, filename, BDRV_O_CACHE_WB | BDRV_O_RDWR, &bdrv_qcow2);
+ preallocate(bs);
+ bdrv_close(bs);
+ }
+
+ return ret;
+}
+
+static int qcow_create(const char *filename, QEMUOptionParameter *options)
+{
+ const char *backing_file = NULL;
+ const char *backing_fmt = NULL;
+ uint64_t sectors = 0;
+ int flags = 0;
+ size_t cluster_size = 65536;
+ int prealloc = 0;
+
+ /* Read out options */
+ while (options && options->name) {
+ if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
+ sectors = options->value.n / 512;
+ } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) {
+ backing_file = options->value.s;
+ } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FMT)) {
+ backing_fmt = options->value.s;
+ } else if (!strcmp(options->name, BLOCK_OPT_ENCRYPT)) {
+ flags |= options->value.n ? BLOCK_FLAG_ENCRYPT : 0;
+ } else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) {
+ if (options->value.n) {
+ cluster_size = options->value.n;
+ }
+ } else if (!strcmp(options->name, BLOCK_OPT_PREALLOC)) {
+ if (!options->value.s || !strcmp(options->value.s, "off")) {
+ prealloc = 0;
+ } else if (!strcmp(options->value.s, "metadata")) {
+ prealloc = 1;
+ } else {
+ fprintf(stderr, "Invalid preallocation mode: '%s'\n",
+ options->value.s);
+ return -EINVAL;
+ }
+ }
+ options++;
+ }
+
+ if (backing_file && prealloc) {
+ fprintf(stderr, "Backing file and preallocation cannot be used at "
+ "the same time\n");
+ return -EINVAL;
+ }
+
+ return qcow_create2(filename, sectors, backing_file, backing_fmt, flags,
+ cluster_size, prealloc);
+}
+
static int qcow_make_empty(BlockDriverState *bs)
{
#if 0
@@ -1105,250 +1349,6 @@ static BlockDriver bdrv_qcow2 = {
.bdrv_check = qcow_check,
};
-static int qcow_create2(const char *filename, int64_t total_size,
- const char *backing_file, const char *backing_format,
- int flags, size_t cluster_size, int prealloc)
-{
-
- int fd, header_size, backing_filename_len, l1_size, i, shift, l2_bits;
- int ref_clusters, reftable_clusters, backing_format_len = 0;
- int rounded_ext_bf_len = 0;
- QCowHeader header;
- uint64_t tmp, offset;
- uint64_t old_ref_clusters;
- QCowCreateState s1, *s = &s1;
- QCowExtension ext_bf = {0, 0};
- int ret;
-
- memset(s, 0, sizeof(*s));
-
- fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644);
- if (fd < 0)
- return -errno;
- memset(&header, 0, sizeof(header));
- header.magic = cpu_to_be32(QCOW_MAGIC);
- header.version = cpu_to_be32(QCOW_VERSION);
- header.size = cpu_to_be64(total_size * 512);
- header_size = sizeof(header);
- backing_filename_len = 0;
- if (backing_file) {
- if (backing_format) {
- ext_bf.magic = QCOW_EXT_MAGIC_BACKING_FORMAT;
- backing_format_len = strlen(backing_format);
- ext_bf.len = backing_format_len;
- rounded_ext_bf_len = (sizeof(ext_bf) + ext_bf.len + 7) & ~7;
- header_size += rounded_ext_bf_len;
- }
- header.backing_file_offset = cpu_to_be64(header_size);
- backing_filename_len = strlen(backing_file);
- header.backing_file_size = cpu_to_be32(backing_filename_len);
- header_size += backing_filename_len;
- }
-
- /* Cluster size */
- s->cluster_bits = get_bits_from_size(cluster_size);
- if (s->cluster_bits < MIN_CLUSTER_BITS ||
- s->cluster_bits > MAX_CLUSTER_BITS)
- {
- fprintf(stderr, "Cluster size must be a power of two between "
- "%d and %dk\n",
- 1 << MIN_CLUSTER_BITS,
- 1 << (MAX_CLUSTER_BITS - 10));
- return -EINVAL;
- }
- s->cluster_size = 1 << s->cluster_bits;
-
- header.cluster_bits = cpu_to_be32(s->cluster_bits);
- header_size = (header_size + 7) & ~7;
- if (flags & BLOCK_FLAG_ENCRYPT) {
- header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES);
- } else {
- header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE);
- }
- l2_bits = s->cluster_bits - 3;
- shift = s->cluster_bits + l2_bits;
- l1_size = (((total_size * 512) + (1LL << shift) - 1) >> shift);
- offset = align_offset(header_size, s->cluster_size);
- s->l1_table_offset = offset;
- header.l1_table_offset = cpu_to_be64(s->l1_table_offset);
- header.l1_size = cpu_to_be32(l1_size);
- offset += align_offset(l1_size * sizeof(uint64_t), s->cluster_size);
-
- /* count how many refcount blocks needed */
-
-#define NUM_CLUSTERS(bytes) \
- (((bytes) + (s->cluster_size) - 1) / (s->cluster_size))
-
- ref_clusters = NUM_CLUSTERS(NUM_CLUSTERS(offset) * sizeof(uint16_t));
-
- do {
- uint64_t image_clusters;
- old_ref_clusters = ref_clusters;
-
- /* Number of clusters used for the refcount table */
- reftable_clusters = NUM_CLUSTERS(ref_clusters * sizeof(uint64_t));
-
- /* Number of clusters that the whole image will have */
- image_clusters = NUM_CLUSTERS(offset) + ref_clusters
- + reftable_clusters;
-
- /* Number of refcount blocks needed for the image */
- ref_clusters = NUM_CLUSTERS(image_clusters * sizeof(uint16_t));
-
- } while (ref_clusters != old_ref_clusters);
-
- s->refcount_table = qemu_mallocz(reftable_clusters * s->cluster_size);
-
- s->refcount_table_offset = offset;
- header.refcount_table_offset = cpu_to_be64(offset);
- header.refcount_table_clusters = cpu_to_be32(reftable_clusters);
- offset += (reftable_clusters * s->cluster_size);
- s->refcount_block_offset = offset;
-
- for (i=0; i < ref_clusters; i++) {
- s->refcount_table[i] = cpu_to_be64(offset);
- offset += s->cluster_size;
- }
-
- s->refcount_block = qemu_mallocz(ref_clusters * s->cluster_size);
-
- /* update refcounts */
- qcow2_create_refcount_update(s, 0, header_size);
- qcow2_create_refcount_update(s, s->l1_table_offset,
- l1_size * sizeof(uint64_t));
- qcow2_create_refcount_update(s, s->refcount_table_offset,
- reftable_clusters * s->cluster_size);
- qcow2_create_refcount_update(s, s->refcount_block_offset,
- ref_clusters * s->cluster_size);
-
- /* write all the data */
- ret = qemu_write_full(fd, &header, sizeof(header));
- if (ret != sizeof(header)) {
- ret = -errno;
- goto exit;
- }
- if (backing_file) {
- if (backing_format_len) {
- char zero[16];
- int padding = rounded_ext_bf_len - (ext_bf.len + sizeof(ext_bf));
-
- memset(zero, 0, sizeof(zero));
- cpu_to_be32s(&ext_bf.magic);
- cpu_to_be32s(&ext_bf.len);
- ret = qemu_write_full(fd, &ext_bf, sizeof(ext_bf));
- if (ret != sizeof(ext_bf)) {
- ret = -errno;
- goto exit;
- }
- ret = qemu_write_full(fd, backing_format, backing_format_len);
- if (ret != backing_format_len) {
- ret = -errno;
- goto exit;
- }
- if (padding > 0) {
- ret = qemu_write_full(fd, zero, padding);
- if (ret != padding) {
- ret = -errno;
- goto exit;
- }
- }
- }
- ret = qemu_write_full(fd, backing_file, backing_filename_len);
- if (ret != backing_filename_len) {
- ret = -errno;
- goto exit;
- }
- }
- lseek(fd, s->l1_table_offset, SEEK_SET);
- tmp = 0;
- for(i = 0;i < l1_size; i++) {
- ret = qemu_write_full(fd, &tmp, sizeof(tmp));
- if (ret != sizeof(tmp)) {
- ret = -errno;
- goto exit;
- }
- }
- lseek(fd, s->refcount_table_offset, SEEK_SET);
- ret = qemu_write_full(fd, s->refcount_table,
- reftable_clusters * s->cluster_size);
- if (ret != reftable_clusters * s->cluster_size) {
- ret = -errno;
- goto exit;
- }
-
- lseek(fd, s->refcount_block_offset, SEEK_SET);
- ret = qemu_write_full(fd, s->refcount_block,
- ref_clusters * s->cluster_size);
- if (ret != ref_clusters * s->cluster_size) {
- ret = -errno;
- goto exit;
- }
-
- ret = 0;
-exit:
- qemu_free(s->refcount_table);
- qemu_free(s->refcount_block);
- close(fd);
-
- /* Preallocate metadata */
- if (ret == 0 && prealloc) {
- BlockDriverState *bs;
- bs = bdrv_new("");
- bdrv_open(bs, filename, BDRV_O_CACHE_WB | BDRV_O_RDWR, &bdrv_qcow2);
- preallocate(bs);
- bdrv_close(bs);
- }
-
- return ret;
-}
-
-static int qcow_create(const char *filename, QEMUOptionParameter *options)
-{
- const char *backing_file = NULL;
- const char *backing_fmt = NULL;
- uint64_t sectors = 0;
- int flags = 0;
- size_t cluster_size = 65536;
- int prealloc = 0;
-
- /* Read out options */
- while (options && options->name) {
- if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
- sectors = options->value.n / 512;
- } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) {
- backing_file = options->value.s;
- } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FMT)) {
- backing_fmt = options->value.s;
- } else if (!strcmp(options->name, BLOCK_OPT_ENCRYPT)) {
- flags |= options->value.n ? BLOCK_FLAG_ENCRYPT : 0;
- } else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) {
- if (options->value.n) {
- cluster_size = options->value.n;
- }
- } else if (!strcmp(options->name, BLOCK_OPT_PREALLOC)) {
- if (!options->value.s || !strcmp(options->value.s, "off")) {
- prealloc = 0;
- } else if (!strcmp(options->value.s, "metadata")) {
- prealloc = 1;
- } else {
- fprintf(stderr, "Invalid preallocation mode: '%s'\n",
- options->value.s);
- return -EINVAL;
- }
- }
- options++;
- }
-
- if (backing_file && prealloc) {
- fprintf(stderr, "Backing file and preallocation cannot be used at "
- "the same time\n");
- return -EINVAL;
- }
-
- return qcow_create2(filename, sectors, backing_file, backing_fmt, flags,
- cluster_size, prealloc);
-}
-
static void bdrv_qcow2_init(void)
{
bdrv_register(&bdrv_qcow2);
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-15 23:06:52 +0000