]> git.proxmox.com Git - mirror_qemu.git/blobdiff - block/qcow.c
Merge remote-tracking branch 'remotes/kraxel/tags/ui-20181029-pull-request' into...
[mirror_qemu.git] / block / qcow.c
index 47a18d9a3a3cf4a20c3418967ad71cd7e41ec052..385d935258f04bbb007e90b4f1eecef5a0f01cec 100644 (file)
@@ -26,6 +26,7 @@
 #include "qapi/error.h"
 #include "qemu/error-report.h"
 #include "block/block_int.h"
+#include "block/qdict.h"
 #include "sysemu/block-backend.h"
 #include "qemu/module.h"
 #include "qemu/option.h"
 #include <zlib.h>
 #include "qapi/qmp/qdict.h"
 #include "qapi/qmp/qstring.h"
+#include "qapi/qobject-input-visitor.h"
+#include "qapi/qapi-visit-block-core.h"
 #include "crypto/block.h"
 #include "migration/blocker.h"
-#include "block/crypto.h"
+#include "crypto.h"
 
 /**************************************************************/
 /* QEMU COW block driver with compression and encryption support */
@@ -67,7 +70,6 @@ typedef struct QCowHeader {
 typedef struct BDRVQcowState {
     int cluster_bits;
     int cluster_size;
-    int cluster_sectors;
     int l2_bits;
     int l2_size;
     unsigned int l1_size;
@@ -86,6 +88,8 @@ typedef struct BDRVQcowState {
     Error *migration_blocker;
 } BDRVQcowState;
 
+static QemuOptsList qcow_create_opts;
+
 static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
 
 static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename)
@@ -198,9 +202,8 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
                 ret = -EINVAL;
                 goto fail;
             }
-            qdict_del(encryptopts, "format");
-            crypto_opts = block_crypto_open_opts_init(
-                Q_CRYPTO_BLOCK_FORMAT_QCOW, encryptopts, errp);
+            qdict_put_str(encryptopts, "format", "qcow");
+            crypto_opts = block_crypto_open_opts_init(encryptopts, errp);
             if (!crypto_opts) {
                 ret = -EINVAL;
                 goto fail;
@@ -231,7 +234,6 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
     }
     s->cluster_bits = header.cluster_bits;
     s->cluster_size = 1 << s->cluster_bits;
-    s->cluster_sectors = 1 << (s->cluster_bits - 9);
     s->l2_bits = header.l2_bits;
     s->l2_size = 1 << s->l2_bits;
     bs->total_sectors = header.size / 512;
@@ -311,7 +313,7 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
         goto fail;
     }
 
-    QDECREF(encryptopts);
+    qobject_unref(encryptopts);
     qapi_free_QCryptoBlockOpenOptions(crypto_opts);
     qemu_co_mutex_init(&s->lock);
     return 0;
@@ -322,7 +324,7 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
     g_free(s->cluster_cache);
     g_free(s->cluster_data);
     qcrypto_block_free(s->crypto);
-    QDECREF(encryptopts);
+    qobject_unref(encryptopts);
     qapi_free_QCryptoBlockOpenOptions(crypto_opts);
     return ret;
 }
@@ -341,8 +343,8 @@ static int qcow_reopen_prepare(BDRVReopenState *state,
  *
  * 0 to not allocate.
  *
- * 1 to allocate a normal cluster (for sector indexes 'n_start' to
- * 'n_end')
+ * 1 to allocate a normal cluster (for sector-aligned byte offsets 'n_start'
+ * to 'n_end' within the cluster)
  *
  * 2 to allocate a compressed cluster of size
  * 'compressed_size'. 'compressed_size' must be > 0 and <
@@ -436,9 +438,10 @@ static int get_cluster_offset(BlockDriverState *bs,
         if (!allocate)
             return 0;
         BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC);
+        assert(QEMU_IS_ALIGNED(n_start | n_end, BDRV_SECTOR_SIZE));
         /* allocate a new cluster */
         if ((cluster_offset & QCOW_OFLAG_COMPRESSED) &&
-            (n_end - n_start) < s->cluster_sectors) {
+            (n_end - n_start) < s->cluster_size) {
             /* if the cluster is already compressed, we must
                decompress it in the case it is not completely
                overwritten */
@@ -476,16 +479,15 @@ static int get_cluster_offset(BlockDriverState *bs,
                 /* if encrypted, we must initialize the cluster
                    content which won't be written */
                 if (bs->encrypted &&
-                    (n_end - n_start) < s->cluster_sectors) {
-                    uint64_t start_sect;
+                    (n_end - n_start) < s->cluster_size) {
+                    uint64_t start_offset;
                     assert(s->crypto);
-                    start_sect = (offset & ~(s->cluster_size - 1)) >> 9;
-                    for(i = 0; i < s->cluster_sectors; i++) {
+                    start_offset = offset & ~(s->cluster_size - 1);
+                    for (i = 0; i < s->cluster_size; i += BDRV_SECTOR_SIZE) {
                         if (i < n_start || i >= n_end) {
-                            memset(s->cluster_data, 0x00, 512);
+                            memset(s->cluster_data, 0x00, BDRV_SECTOR_SIZE);
                             if (qcrypto_block_encrypt(s->crypto,
-                                                      (start_sect + i) *
-                                                      BDRV_SECTOR_SIZE,
+                                                      start_offset + i,
                                                       s->cluster_data,
                                                       BDRV_SECTOR_SIZE,
                                                       NULL) < 0) {
@@ -493,8 +495,9 @@ static int get_cluster_offset(BlockDriverState *bs,
                             }
                             BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO);
                             ret = bdrv_pwrite(bs->file,
-                                              cluster_offset + i * 512,
-                                              s->cluster_data, 512);
+                                              cluster_offset + i,
+                                              s->cluster_data,
+                                              BDRV_SECTOR_SIZE);
                             if (ret < 0) {
                                 return ret;
                             }
@@ -608,11 +611,21 @@ static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset)
     return 0;
 }
 
-static coroutine_fn int qcow_co_readv(BlockDriverState *bs, int64_t sector_num,
-                         int nb_sectors, QEMUIOVector *qiov)
+static void qcow_refresh_limits(BlockDriverState *bs, Error **errp)
+{
+    /* At least encrypted images require 512-byte alignment. Apply the
+     * limit universally, rather than just on encrypted images, as
+     * it's easier to let the block layer handle rounding than to
+     * audit this code further. */
+    bs->bl.request_alignment = BDRV_SECTOR_SIZE;
+}
+
+static coroutine_fn int qcow_co_preadv(BlockDriverState *bs, uint64_t offset,
+                                       uint64_t bytes, QEMUIOVector *qiov,
+                                       int flags)
 {
     BDRVQcowState *s = bs->opaque;
-    int index_in_cluster;
+    int offset_in_cluster;
     int ret = 0, n;
     uint64_t cluster_offset;
     struct iovec hd_iov;
@@ -620,6 +633,7 @@ static coroutine_fn int qcow_co_readv(BlockDriverState *bs, int64_t sector_num,
     uint8_t *buf;
     void *orig_buf;
 
+    assert(!flags);
     if (qiov->niov > 1) {
         buf = orig_buf = qemu_try_blockalign(bs, qiov->size);
         if (buf == NULL) {
@@ -632,36 +646,35 @@ static coroutine_fn int qcow_co_readv(BlockDriverState *bs, int64_t sector_num,
 
     qemu_co_mutex_lock(&s->lock);
 
-    while (nb_sectors != 0) {
+    while (bytes != 0) {
         /* prepare next request */
-        ret = get_cluster_offset(bs, sector_num << 9,
-                                 0, 0, 0, 0, &cluster_offset);
+        ret = get_cluster_offset(bs, offset, 0, 0, 0, 0, &cluster_offset);
         if (ret < 0) {
             break;
         }
-        index_in_cluster = sector_num & (s->cluster_sectors - 1);
-        n = s->cluster_sectors - index_in_cluster;
-        if (n > nb_sectors) {
-            n = nb_sectors;
+        offset_in_cluster = offset & (s->cluster_size - 1);
+        n = s->cluster_size - offset_in_cluster;
+        if (n > bytes) {
+            n = bytes;
         }
 
         if (!cluster_offset) {
             if (bs->backing) {
                 /* read from the base image */
                 hd_iov.iov_base = (void *)buf;
-                hd_iov.iov_len = n * 512;
+                hd_iov.iov_len = n;
                 qemu_iovec_init_external(&hd_qiov, &hd_iov, 1);
                 qemu_co_mutex_unlock(&s->lock);
                 /* qcow2 emits this on bs->file instead of bs->backing */
                 BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO);
-                ret = bdrv_co_readv(bs->backing, sector_num, n, &hd_qiov);
+                ret = bdrv_co_preadv(bs->backing, offset, n, &hd_qiov, 0);
                 qemu_co_mutex_lock(&s->lock);
                 if (ret < 0) {
                     break;
                 }
             } else {
                 /* Note: in this case, no need to wait */
-                memset(buf, 0, 512 * n);
+                memset(buf, 0, n);
             }
         } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
             /* add AIO support for compressed blocks ? */
@@ -669,21 +682,19 @@ static coroutine_fn int qcow_co_readv(BlockDriverState *bs, int64_t sector_num,
                 ret = -EIO;
                 break;
             }
-            memcpy(buf,
-                   s->cluster_cache + index_in_cluster * 512, 512 * n);
+            memcpy(buf, s->cluster_cache + offset_in_cluster, n);
         } else {
             if ((cluster_offset & 511) != 0) {
                 ret = -EIO;
                 break;
             }
             hd_iov.iov_base = (void *)buf;
-            hd_iov.iov_len = n * 512;
+            hd_iov.iov_len = n;
             qemu_iovec_init_external(&hd_qiov, &hd_iov, 1);
             qemu_co_mutex_unlock(&s->lock);
             BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO);
-            ret = bdrv_co_readv(bs->file,
-                                (cluster_offset >> 9) + index_in_cluster,
-                                n, &hd_qiov);
+            ret = bdrv_co_preadv(bs->file, cluster_offset + offset_in_cluster,
+                                 n, &hd_qiov, 0);
             qemu_co_mutex_lock(&s->lock);
             if (ret < 0) {
                 break;
@@ -691,8 +702,7 @@ static coroutine_fn int qcow_co_readv(BlockDriverState *bs, int64_t sector_num,
             if (bs->encrypted) {
                 assert(s->crypto);
                 if (qcrypto_block_decrypt(s->crypto,
-                                          sector_num * BDRV_SECTOR_SIZE, buf,
-                                          n * BDRV_SECTOR_SIZE, NULL) < 0) {
+                                          offset, buf, n, NULL) < 0) {
                     ret = -EIO;
                     break;
                 }
@@ -700,9 +710,9 @@ static coroutine_fn int qcow_co_readv(BlockDriverState *bs, int64_t sector_num,
         }
         ret = 0;
 
-        nb_sectors -= n;
-        sector_num += n;
-        buf += n * 512;
+        bytes -= n;
+        offset += n;
+        buf += n;
     }
 
     qemu_co_mutex_unlock(&s->lock);
@@ -715,11 +725,12 @@ static coroutine_fn int qcow_co_readv(BlockDriverState *bs, int64_t sector_num,
     return ret;
 }
 
-static coroutine_fn int qcow_co_writev(BlockDriverState *bs, int64_t sector_num,
-                          int nb_sectors, QEMUIOVector *qiov)
+static coroutine_fn int qcow_co_pwritev(BlockDriverState *bs, uint64_t offset,
+                                        uint64_t bytes, QEMUIOVector *qiov,
+                                        int flags)
 {
     BDRVQcowState *s = bs->opaque;
-    int index_in_cluster;
+    int offset_in_cluster;
     uint64_t cluster_offset;
     int ret = 0, n;
     struct iovec hd_iov;
@@ -727,6 +738,7 @@ static coroutine_fn int qcow_co_writev(BlockDriverState *bs, int64_t sector_num,
     uint8_t *buf;
     void *orig_buf;
 
+    assert(!flags);
     s->cluster_cache_offset = -1; /* disable compressed cache */
 
     /* We must always copy the iov when encrypting, so we
@@ -744,16 +756,14 @@ static coroutine_fn int qcow_co_writev(BlockDriverState *bs, int64_t sector_num,
 
     qemu_co_mutex_lock(&s->lock);
 
-    while (nb_sectors != 0) {
-
-        index_in_cluster = sector_num & (s->cluster_sectors - 1);
-        n = s->cluster_sectors - index_in_cluster;
-        if (n > nb_sectors) {
-            n = nb_sectors;
+    while (bytes != 0) {
+        offset_in_cluster = offset & (s->cluster_size - 1);
+        n = s->cluster_size - offset_in_cluster;
+        if (n > bytes) {
+            n = bytes;
         }
-        ret = get_cluster_offset(bs, sector_num << 9, 1, 0,
-                                 index_in_cluster,
-                                 index_in_cluster + n, &cluster_offset);
+        ret = get_cluster_offset(bs, offset, 1, 0, offset_in_cluster,
+                                 offset_in_cluster + n, &cluster_offset);
         if (ret < 0) {
             break;
         }
@@ -763,30 +773,28 @@ static coroutine_fn int qcow_co_writev(BlockDriverState *bs, int64_t sector_num,
         }
         if (bs->encrypted) {
             assert(s->crypto);
-            if (qcrypto_block_encrypt(s->crypto, sector_num * BDRV_SECTOR_SIZE,
-                                      buf, n * BDRV_SECTOR_SIZE, NULL) < 0) {
+            if (qcrypto_block_encrypt(s->crypto, offset, buf, n, NULL) < 0) {
                 ret = -EIO;
                 break;
             }
         }
 
         hd_iov.iov_base = (void *)buf;
-        hd_iov.iov_len = n * 512;
+        hd_iov.iov_len = n;
         qemu_iovec_init_external(&hd_qiov, &hd_iov, 1);
         qemu_co_mutex_unlock(&s->lock);
         BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO);
-        ret = bdrv_co_writev(bs->file,
-                             (cluster_offset >> 9) + index_in_cluster,
-                             n, &hd_qiov);
+        ret = bdrv_co_pwritev(bs->file, cluster_offset + offset_in_cluster,
+                              n, &hd_qiov, 0);
         qemu_co_mutex_lock(&s->lock);
         if (ret < 0) {
             break;
         }
         ret = 0;
 
-        nb_sectors -= n;
-        sector_num += n;
-        buf += n * 512;
+        bytes -= n;
+        offset += n;
+        buf += n;
     }
     qemu_co_mutex_unlock(&s->lock);
 
@@ -810,62 +818,50 @@ static void qcow_close(BlockDriverState *bs)
     error_free(s->migration_blocker);
 }
 
-static int coroutine_fn qcow_co_create_opts(const char *filename, QemuOpts *opts,
-                                            Error **errp)
+static int coroutine_fn qcow_co_create(BlockdevCreateOptions *opts,
+                                       Error **errp)
 {
+    BlockdevCreateOptionsQcow *qcow_opts;
     int header_size, backing_filename_len, l1_size, shift, i;
     QCowHeader header;
     uint8_t *tmp;
     int64_t total_size = 0;
-    char *backing_file = NULL;
-    Error *local_err = NULL;
     int ret;
+    BlockDriverState *bs;
     BlockBackend *qcow_blk;
-    char *encryptfmt = NULL;
-    QDict *options;
-    QDict *encryptopts = NULL;
-    QCryptoBlockCreateOptions *crypto_opts = NULL;
     QCryptoBlock *crypto = NULL;
 
-    /* Read out options */
-    total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
-                          BDRV_SECTOR_SIZE);
+    assert(opts->driver == BLOCKDEV_DRIVER_QCOW);
+    qcow_opts = &opts->u.qcow;
+
+    /* Sanity checks */
+    total_size = qcow_opts->size;
     if (total_size == 0) {
         error_setg(errp, "Image size is too small, cannot be zero length");
-        ret = -EINVAL;
-        goto cleanup;
+        return -EINVAL;
     }
 
-    backing_file = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FILE);
-    encryptfmt = qemu_opt_get_del(opts, BLOCK_OPT_ENCRYPT_FORMAT);
-    if (encryptfmt) {
-        if (qemu_opt_get(opts, BLOCK_OPT_ENCRYPT)) {
-            error_setg(errp, "Options " BLOCK_OPT_ENCRYPT " and "
-                       BLOCK_OPT_ENCRYPT_FORMAT " are mutually exclusive");
-            ret = -EINVAL;
-            goto cleanup;
-        }
-    } else if (qemu_opt_get_bool_del(opts, BLOCK_OPT_ENCRYPT, false)) {
-        encryptfmt = g_strdup("aes");
+    if (qcow_opts->has_encrypt &&
+        qcow_opts->encrypt->format != Q_CRYPTO_BLOCK_FORMAT_QCOW)
+    {
+        error_setg(errp, "Unsupported encryption format");
+        return -EINVAL;
     }
 
-    ret = bdrv_create_file(filename, opts, &local_err);
-    if (ret < 0) {
-        error_propagate(errp, local_err);
-        goto cleanup;
+    /* Create BlockBackend to write to the image */
+    bs = bdrv_open_blockdev_ref(qcow_opts->file, errp);
+    if (bs == NULL) {
+        return -EIO;
     }
 
-    qcow_blk = blk_new_open(filename, NULL, NULL,
-                            BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL,
-                            &local_err);
-    if (qcow_blk == NULL) {
-        error_propagate(errp, local_err);
-        ret = -EIO;
-        goto cleanup;
+    qcow_blk = blk_new(BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);
+    ret = blk_insert_bs(qcow_blk, bs, errp);
+    if (ret < 0) {
+        goto exit;
     }
-
     blk_set_allow_write_beyond_eof(qcow_blk, true);
 
+    /* Create image format */
     ret = blk_truncate(qcow_blk, 0, PREALLOC_MODE_OFF, errp);
     if (ret < 0) {
         goto exit;
@@ -877,16 +873,15 @@ static int coroutine_fn qcow_co_create_opts(const char *filename, QemuOpts *opts
     header.size = cpu_to_be64(total_size);
     header_size = sizeof(header);
     backing_filename_len = 0;
-    if (backing_file) {
-        if (strcmp(backing_file, "fat:")) {
+    if (qcow_opts->has_backing_file) {
+        if (strcmp(qcow_opts->backing_file, "fat:")) {
             header.backing_file_offset = cpu_to_be64(header_size);
-            backing_filename_len = strlen(backing_file);
+            backing_filename_len = strlen(qcow_opts->backing_file);
             header.backing_file_size = cpu_to_be32(backing_filename_len);
             header_size += backing_filename_len;
         } else {
             /* special backing file for vvfat */
-            g_free(backing_file);
-            backing_file = NULL;
+            qcow_opts->has_backing_file = false;
         }
         header.cluster_bits = 9; /* 512 byte cluster to avoid copying
                                     unmodified sectors */
@@ -901,26 +896,10 @@ static int coroutine_fn qcow_co_create_opts(const char *filename, QemuOpts *opts
 
     header.l1_table_offset = cpu_to_be64(header_size);
 
-    options = qemu_opts_to_qdict(opts, NULL);
-    qdict_extract_subqdict(options, &encryptopts, "encrypt.");
-    QDECREF(options);
-    if (encryptfmt) {
-        if (!g_str_equal(encryptfmt, "aes")) {
-            error_setg(errp, "Unknown encryption format '%s', expected 'aes'",
-                       encryptfmt);
-            ret = -EINVAL;
-            goto exit;
-        }
+    if (qcow_opts->has_encrypt) {
         header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES);
 
-        crypto_opts = block_crypto_create_opts_init(
-            Q_CRYPTO_BLOCK_FORMAT_QCOW, encryptopts, errp);
-        if (!crypto_opts) {
-            ret = -EINVAL;
-            goto exit;
-        }
-
-        crypto = qcrypto_block_create(crypto_opts, "encrypt.",
+        crypto = qcrypto_block_create(qcow_opts->encrypt, "encrypt.",
                                       NULL, NULL, NULL, errp);
         if (!crypto) {
             ret = -EINVAL;
@@ -936,9 +915,9 @@ static int coroutine_fn qcow_co_create_opts(const char *filename, QemuOpts *opts
         goto exit;
     }
 
-    if (backing_file) {
+    if (qcow_opts->has_backing_file) {
         ret = blk_pwrite(qcow_blk, sizeof(header),
-                         backing_file, backing_filename_len, 0);
+                         qcow_opts->backing_file, backing_filename_len, 0);
         if (ret != backing_filename_len) {
             goto exit;
         }
@@ -959,12 +938,97 @@ static int coroutine_fn qcow_co_create_opts(const char *filename, QemuOpts *opts
     ret = 0;
 exit:
     blk_unref(qcow_blk);
-cleanup:
-    QDECREF(encryptopts);
-    g_free(encryptfmt);
+    bdrv_unref(bs);
     qcrypto_block_free(crypto);
-    qapi_free_QCryptoBlockCreateOptions(crypto_opts);
-    g_free(backing_file);
+    return ret;
+}
+
+static int coroutine_fn qcow_co_create_opts(const char *filename,
+                                            QemuOpts *opts, Error **errp)
+{
+    BlockdevCreateOptions *create_options = NULL;
+    BlockDriverState *bs = NULL;
+    QDict *qdict;
+    Visitor *v;
+    const char *val;
+    Error *local_err = NULL;
+    int ret;
+
+    static const QDictRenames opt_renames[] = {
+        { BLOCK_OPT_BACKING_FILE,       "backing-file" },
+        { BLOCK_OPT_ENCRYPT,            BLOCK_OPT_ENCRYPT_FORMAT },
+        { NULL, NULL },
+    };
+
+    /* Parse options and convert legacy syntax */
+    qdict = qemu_opts_to_qdict_filtered(opts, NULL, &qcow_create_opts, true);
+
+    val = qdict_get_try_str(qdict, BLOCK_OPT_ENCRYPT);
+    if (val && !strcmp(val, "on")) {
+        qdict_put_str(qdict, BLOCK_OPT_ENCRYPT, "qcow");
+    } else if (val && !strcmp(val, "off")) {
+        qdict_del(qdict, BLOCK_OPT_ENCRYPT);
+    }
+
+    val = qdict_get_try_str(qdict, BLOCK_OPT_ENCRYPT_FORMAT);
+    if (val && !strcmp(val, "aes")) {
+        qdict_put_str(qdict, BLOCK_OPT_ENCRYPT_FORMAT, "qcow");
+    }
+
+    if (!qdict_rename_keys(qdict, opt_renames, errp)) {
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    /* Create and open the file (protocol layer) */
+    ret = bdrv_create_file(filename, opts, &local_err);
+    if (ret < 0) {
+        error_propagate(errp, local_err);
+        goto fail;
+    }
+
+    bs = bdrv_open(filename, NULL, NULL,
+                   BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, errp);
+    if (bs == NULL) {
+        ret = -EIO;
+        goto fail;
+    }
+
+    /* Now get the QAPI type BlockdevCreateOptions */
+    qdict_put_str(qdict, "driver", "qcow");
+    qdict_put_str(qdict, "file", bs->node_name);
+
+    v = qobject_input_visitor_new_flat_confused(qdict, errp);
+    if (!v) {
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    visit_type_BlockdevCreateOptions(v, NULL, &create_options, &local_err);
+    visit_free(v);
+
+    if (local_err) {
+        error_propagate(errp, local_err);
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    /* Silently round up size */
+    assert(create_options->driver == BLOCKDEV_DRIVER_QCOW);
+    create_options->u.qcow.size =
+        ROUND_UP(create_options->u.qcow.size, BDRV_SECTOR_SIZE);
+
+    /* Create the qcow image (format layer) */
+    ret = qcow_co_create(create_options, errp);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    ret = 0;
+fail:
+    qobject_unref(qdict);
+    bdrv_unref(bs);
+    qapi_free_BlockdevCreateOptions(create_options);
     return ret;
 }
 
@@ -1046,8 +1110,7 @@ qcow_co_pwritev_compressed(BlockDriverState *bs, uint64_t offset,
 
     if (ret != Z_STREAM_END || out_len >= s->cluster_size) {
         /* could not compress: write normal cluster */
-        ret = qcow_co_writev(bs, offset >> BDRV_SECTOR_BITS,
-                             bytes >> BDRV_SECTOR_BITS, qiov);
+        ret = qcow_co_pwritev(bs, offset, bytes, qiov, 0);
         if (ret < 0) {
             goto fail;
         }
@@ -1128,12 +1191,14 @@ static BlockDriver bdrv_qcow = {
     .bdrv_close                = qcow_close,
     .bdrv_child_perm        = bdrv_format_default_perms,
     .bdrv_reopen_prepare    = qcow_reopen_prepare,
+    .bdrv_co_create         = qcow_co_create,
     .bdrv_co_create_opts    = qcow_co_create_opts,
     .bdrv_has_zero_init     = bdrv_has_zero_init_1,
     .supports_backing       = true,
+    .bdrv_refresh_limits    = qcow_refresh_limits,
 
-    .bdrv_co_readv          = qcow_co_readv,
-    .bdrv_co_writev         = qcow_co_writev,
+    .bdrv_co_preadv         = qcow_co_preadv,
+    .bdrv_co_pwritev        = qcow_co_pwritev,
     .bdrv_co_block_status   = qcow_co_block_status,
 
     .bdrv_make_empty        = qcow_make_empty,