diff mbox

[RFC,4/5] block: Open the underlying image file in generic code

Message ID 1271260214-27443-5-git-send-email-kwolf@redhat.com
State New
Headers show

Commit Message

Kevin Wolf April 14, 2010, 3:50 p.m. UTC
Format drivers shouldn't need to bother with things like file names, but rather
just get an open BlockDriverState for the underlying protocol. This patch
introduces this behaviour for bdrv_open implementation. For protocols which
need to access the filename to open their file/device/connection/... a new
callback bdrv_file_open is introduced which doesn't get an underlying file
opened.

For now, also some of the more obscure formats use bdrv_file_open because they
open() the file themselves instead of using the block.c functions. They need to
be fixed in later patches.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block.c                |   25 ++++++++++++++-
 block/blkdebug.c       |   17 +++------
 block/bochs.c          |    2 +-
 block/cloop.c          |    2 +-
 block/cow.c            |    2 +-
 block/curl.c           |   10 +++---
 block/dmg.c            |    2 +-
 block/nbd.c            |    2 +-
 block/parallels.c      |    2 +-
 block/qcow.c           |   69 +++++++++++++++++++----------------------
 block/qcow2-cluster.c  |   64 ++++++++++++++++++++------------------
 block/qcow2-refcount.c |   80 ++++++++++++++++++++++++------------------------
 block/qcow2-snapshot.c |   22 ++++++------
 block/qcow2.c          |   67 +++++++++++++++++-----------------------
 block/qcow2.h          |    2 +-
 block/raw-posix.c      |   10 +++---
 block/raw-win32.c      |    4 +-
 block/raw.c            |   63 +++++++++++---------------------------
 block/vdi.c            |   30 ++++++------------
 block/vmdk.c           |    2 +-
 block/vpc.c            |   34 ++++++++------------
 block/vvfat.c          |    2 +-
 block_int.h            |    5 ++-
 23 files changed, 242 insertions(+), 276 deletions(-)

Comments

Stefan Hajnoczi April 15, 2010, 8:48 a.m. UTC | #1
On Wed, Apr 14, 2010 at 4:50 PM, Kevin Wolf <kwolf@redhat.com> wrote:
> diff --git a/block/qcow.c b/block/qcow.c
> index c619984..01b1692 100644
> --- a/block/qcow.c
> +++ b/block/qcow.c
[..]
> @@ -169,7 +166,7 @@ static int qcow_open(BlockDriverState *bs, const char *filename, int flags)
>     qemu_free(s->l2_cache);
>     qemu_free(s->cluster_cache);
>     qemu_free(s->cluster_data);
> -    bdrv_delete(s->hd);
> +    bdrv_delete(bs->file);
>     return -1;
>  }

qcow.c does not need to delete bs->file anymore because block.c does
that when BlockDriver->bdrv_open() fails.  Also since we're not
setting bs->file to NULL after bdrv_delete() here, block.c will double
delete it.

> @@ -739,7 +737,7 @@ static void qcow_close(BlockDriverState *bs)
>     qemu_free(s->l2_cache);
>     qemu_free(s->cluster_cache);
>     qemu_free(s->cluster_data);
> -    bdrv_delete(s->hd);
> +    bdrv_delete(bs->file);
>  }
>
>  static int qcow_create(const char *filename, QEMUOptionParameter *options)

block.c will bdrv_close(bs->file) for us, so I think this is not
needed.  Double delete.

> diff --git a/block/qcow2.c b/block/qcow2.c
> index 11ce8d1..4949d77 100644
> --- a/block/qcow2.c
> +++ b/block/qcow2.c
[...]
> @@ -254,7 +250,7 @@ static int qcow_open(BlockDriverState *bs, const char *filename, int flags)
>     qemu_free(s->l2_cache);
>     qemu_free(s->cluster_cache);
>     qemu_free(s->cluster_data);
> -    bdrv_delete(s->hd);
> +    bdrv_delete(bs->file);
>     return -1;
>  }

Same as above.

> diff --git a/block/vdi.c b/block/vdi.c
> index c91961a..8b85339 100644
> --- a/block/vdi.c
> +++ b/block/vdi.c
[...]
> @@ -452,7 +446,7 @@ static int vdi_open(BlockDriverState *bs, const char *filename, int flags)
>     qemu_free(s->bmap);
>
>  fail:
> -    bdrv_delete(s->hd);
> +    bdrv_delete(bs->file);
>     return -1;
>  }

Same as above.

> diff --git a/block/vpc.c b/block/vpc.c
> index 950ad58..1d1ae09 100644
> --- a/block/vpc.c
> +++ b/block/vpc.c
[...]
> @@ -228,7 +224,7 @@ static int vpc_open(BlockDriverState *bs, const char *filename, int flags)
>
>     return 0;
>  fail:
> -    bdrv_delete(s->hd);
> +    bdrv_delete(bs->file);
>     return -1;
>  }

Same as above.

> @@ -590,7 +584,7 @@ static void vpc_close(BlockDriverState *bs)
>  #ifdef CACHE
>     qemu_free(s->pageentry_u8);
>  #endif
> -    bdrv_delete(s->hd);
> +    bdrv_delete(bs->file);
>  }
>
>  static QEMUOptionParameter vpc_create_options[] = {

Same as above.

Stefan
diff mbox

Patch

diff --git a/block.c b/block.c
index fd70d64..6c66974 100644
--- a/block.c
+++ b/block.c
@@ -288,6 +288,8 @@  static BlockDriver *find_protocol(const char *filename)
     int len;
     const char *p;
 
+    /* TODO Drivers without bdrv_file_open must be specified explicitly */
+
 #ifdef _WIN32
     if (is_windows_drive(filename) ||
         is_windows_drive_prefix(filename))
@@ -398,7 +400,16 @@  static int bdrv_open_common(BlockDriverState *bs, const char *filename,
         open_flags |= BDRV_O_RDWR;
     }
 
-    ret = drv->bdrv_open(bs, filename, open_flags);
+    /* Open the image, either directly or using a protocol */
+    if (drv->bdrv_file_open) {
+        ret = drv->bdrv_file_open(bs, filename, open_flags);
+    } else {
+        ret = bdrv_file_open(&bs->file, filename, open_flags);
+        if (ret >= 0) {
+            ret = drv->bdrv_open(bs, open_flags);
+        }
+    }
+
     if (ret < 0) {
         goto free_and_fail;
     }
@@ -415,6 +426,10 @@  static int bdrv_open_common(BlockDriverState *bs, const char *filename,
     return 0;
 
 free_and_fail:
+    if (bs->file) {
+        bdrv_delete(bs->file);
+        bs->file = NULL;
+    }
     qemu_free(bs->opaque);
     bs->opaque = NULL;
     bs->drv = NULL;
@@ -585,6 +600,10 @@  void bdrv_close(BlockDriverState *bs)
         bs->opaque = NULL;
         bs->drv = NULL;
 
+        if (bs->file != NULL) {
+            bdrv_close(bs->file);
+        }
+
         /* call the change callback */
         bs->media_changed = 1;
         if (bs->change_cb)
@@ -600,6 +619,10 @@  void bdrv_delete(BlockDriverState *bs)
     }
 
     bdrv_close(bs);
+    if (bs->file != NULL) {
+        bdrv_delete(bs->file);
+    }
+
     qemu_free(bs);
 }
 
diff --git a/block/blkdebug.c b/block/blkdebug.c
index 643c397..bb4a91a 100644
--- a/block/blkdebug.c
+++ b/block/blkdebug.c
@@ -44,7 +44,6 @@  typedef struct BlkdebugVars {
 } BlkdebugVars;
 
 typedef struct BDRVBlkdebugState {
-    BlockDriverState *hd;
     BlkdebugVars vars;
     QLIST_HEAD(list, BlkdebugRule) rules[BLKDBG_EVENT_MAX];
 } BDRVBlkdebugState;
@@ -303,7 +302,7 @@  static int blkdebug_open(BlockDriverState *bs, const char *filename, int flags)
     filename = c + 1;
 
     /* Open the backing file */
-    ret = bdrv_file_open(&s->hd, filename, flags);
+    ret = bdrv_file_open(&bs->file, filename, flags);
     if (ret < 0) {
         return ret;
     }
@@ -362,7 +361,7 @@  static BlockDriverAIOCB *blkdebug_aio_readv(BlockDriverState *bs,
     }
 
     BlockDriverAIOCB *acb =
-        bdrv_aio_readv(s->hd, sector_num, qiov, nb_sectors, cb, opaque);
+        bdrv_aio_readv(bs->file, sector_num, qiov, nb_sectors, cb, opaque);
     return acb;
 }
 
@@ -377,7 +376,7 @@  static BlockDriverAIOCB *blkdebug_aio_writev(BlockDriverState *bs,
     }
 
     BlockDriverAIOCB *acb =
-        bdrv_aio_writev(s->hd, sector_num, qiov, nb_sectors, cb, opaque);
+        bdrv_aio_writev(bs->file, sector_num, qiov, nb_sectors, cb, opaque);
     return acb;
 }
 
@@ -393,21 +392,17 @@  static void blkdebug_close(BlockDriverState *bs)
             qemu_free(rule);
         }
     }
-
-    bdrv_delete(s->hd);
 }
 
 static void blkdebug_flush(BlockDriverState *bs)
 {
-    BDRVBlkdebugState *s = bs->opaque;
-    bdrv_flush(s->hd);
+    bdrv_flush(bs->file);
 }
 
 static BlockDriverAIOCB *blkdebug_aio_flush(BlockDriverState *bs,
     BlockDriverCompletionFunc *cb, void *opaque)
 {
-    BDRVBlkdebugState *s = bs->opaque;
-    return bdrv_aio_flush(s->hd, cb, opaque);
+    return bdrv_aio_flush(bs->file, cb, opaque);
 }
 
 static void process_rule(BlockDriverState *bs, struct BlkdebugRule *rule,
@@ -456,7 +451,7 @@  static BlockDriver bdrv_blkdebug = {
 
     .instance_size      = sizeof(BDRVBlkdebugState),
 
-    .bdrv_open          = blkdebug_open,
+    .bdrv_file_open     = blkdebug_open,
     .bdrv_close         = blkdebug_close,
     .bdrv_flush         = blkdebug_flush,
 
diff --git a/block/bochs.c b/block/bochs.c
index 843008f..c8f921f 100644
--- a/block/bochs.c
+++ b/block/bochs.c
@@ -254,7 +254,7 @@  static BlockDriver bdrv_bochs = {
     .format_name	= "bochs",
     .instance_size	= sizeof(BDRVBochsState),
     .bdrv_probe		= bochs_probe,
-    .bdrv_open		= bochs_open,
+    .bdrv_file_open	= bochs_open,
     .bdrv_read		= bochs_read,
     .bdrv_close		= bochs_close,
 };
diff --git a/block/cloop.c b/block/cloop.c
index bf1b9b4..96cbb89 100644
--- a/block/cloop.c
+++ b/block/cloop.c
@@ -161,7 +161,7 @@  static BlockDriver bdrv_cloop = {
     .format_name	= "cloop",
     .instance_size	= sizeof(BDRVCloopState),
     .bdrv_probe		= cloop_probe,
-    .bdrv_open		= cloop_open,
+    .bdrv_file_open	= cloop_open,
     .bdrv_read		= cloop_read,
     .bdrv_close		= cloop_close,
 };
diff --git a/block/cow.c b/block/cow.c
index 97e9745..fde066e 100644
--- a/block/cow.c
+++ b/block/cow.c
@@ -291,7 +291,7 @@  static BlockDriver bdrv_cow = {
     .format_name	= "cow",
     .instance_size	= sizeof(BDRVCowState),
     .bdrv_probe		= cow_probe,
-    .bdrv_open		= cow_open,
+    .bdrv_file_open	= cow_open,
     .bdrv_read		= cow_read,
     .bdrv_write		= cow_write,
     .bdrv_close		= cow_close,
diff --git a/block/curl.c b/block/curl.c
index 2cf72cb..b944740 100644
--- a/block/curl.c
+++ b/block/curl.c
@@ -495,7 +495,7 @@  static BlockDriver bdrv_http = {
     .protocol_name   = "http",
 
     .instance_size   = sizeof(BDRVCURLState),
-    .bdrv_open       = curl_open,
+    .bdrv_file_open  = curl_open,
     .bdrv_close      = curl_close,
     .bdrv_getlength  = curl_getlength,
 
@@ -507,7 +507,7 @@  static BlockDriver bdrv_https = {
     .protocol_name   = "https",
 
     .instance_size   = sizeof(BDRVCURLState),
-    .bdrv_open       = curl_open,
+    .bdrv_file_open  = curl_open,
     .bdrv_close      = curl_close,
     .bdrv_getlength  = curl_getlength,
 
@@ -519,7 +519,7 @@  static BlockDriver bdrv_ftp = {
     .protocol_name   = "ftp",
 
     .instance_size   = sizeof(BDRVCURLState),
-    .bdrv_open       = curl_open,
+    .bdrv_file_open  = curl_open,
     .bdrv_close      = curl_close,
     .bdrv_getlength  = curl_getlength,
 
@@ -531,7 +531,7 @@  static BlockDriver bdrv_ftps = {
     .protocol_name   = "ftps",
 
     .instance_size   = sizeof(BDRVCURLState),
-    .bdrv_open       = curl_open,
+    .bdrv_file_open  = curl_open,
     .bdrv_close      = curl_close,
     .bdrv_getlength  = curl_getlength,
 
@@ -543,7 +543,7 @@  static BlockDriver bdrv_tftp = {
     .protocol_name   = "tftp",
 
     .instance_size   = sizeof(BDRVCURLState),
-    .bdrv_open       = curl_open,
+    .bdrv_file_open  = curl_open,
     .bdrv_close      = curl_close,
     .bdrv_getlength  = curl_getlength,
 
diff --git a/block/dmg.c b/block/dmg.c
index dbb4eda..f65b5f5 100644
--- a/block/dmg.c
+++ b/block/dmg.c
@@ -291,7 +291,7 @@  static BlockDriver bdrv_dmg = {
     .format_name	= "dmg",
     .instance_size	= sizeof(BDRVDMGState),
     .bdrv_probe		= dmg_probe,
-    .bdrv_open		= dmg_open,
+    .bdrv_file_open	= dmg_open,
     .bdrv_read		= dmg_read,
     .bdrv_close		= dmg_close,
 };
diff --git a/block/nbd.c b/block/nbd.c
index 7bac38d..a1ec123 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -177,7 +177,7 @@  static int64_t nbd_getlength(BlockDriverState *bs)
 static BlockDriver bdrv_nbd = {
     .format_name	= "nbd",
     .instance_size	= sizeof(BDRVNBDState),
-    .bdrv_open		= nbd_open,
+    .bdrv_file_open	= nbd_open,
     .bdrv_read		= nbd_read,
     .bdrv_write		= nbd_write,
     .bdrv_close		= nbd_close,
diff --git a/block/parallels.c b/block/parallels.c
index b6312a6..3d04965 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -169,7 +169,7 @@  static BlockDriver bdrv_parallels = {
     .format_name	= "parallels",
     .instance_size	= sizeof(BDRVParallelsState),
     .bdrv_probe		= parallels_probe,
-    .bdrv_open		= parallels_open,
+    .bdrv_file_open	= parallels_open,
     .bdrv_read		= parallels_read,
     .bdrv_close		= parallels_close,
 };
diff --git a/block/qcow.c b/block/qcow.c
index c619984..01b1692 100644
--- a/block/qcow.c
+++ b/block/qcow.c
@@ -76,7 +76,7 @@  typedef struct BDRVQcowState {
     AES_KEY aes_decrypt_key;
 } BDRVQcowState;
 
-static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset);
+static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
 
 static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename)
 {
@@ -90,16 +90,13 @@  static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename)
         return 0;
 }
 
-static int qcow_open(BlockDriverState *bs, const char *filename, int flags)
+static int qcow_open(BlockDriverState *bs, int flags)
 {
     BDRVQcowState *s = bs->opaque;
-    int len, i, shift, ret;
+    int len, i, shift;
     QCowHeader header;
 
-    ret = bdrv_file_open(&s->hd, filename, flags);
-    if (ret < 0)
-        return ret;
-    if (bdrv_pread(s->hd, 0, &header, sizeof(header)) != sizeof(header))
+    if (bdrv_pread(bs->file, 0, &header, sizeof(header)) != sizeof(header))
         goto fail;
     be32_to_cpus(&header.magic);
     be32_to_cpus(&header.version);
@@ -135,7 +132,7 @@  static int qcow_open(BlockDriverState *bs, const char *filename, int flags)
     s->l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t));
     if (!s->l1_table)
         goto fail;
-    if (bdrv_pread(s->hd, s->l1_table_offset, s->l1_table, s->l1_size * sizeof(uint64_t)) !=
+    if (bdrv_pread(bs->file, s->l1_table_offset, s->l1_table, s->l1_size * sizeof(uint64_t)) !=
         s->l1_size * sizeof(uint64_t))
         goto fail;
     for(i = 0;i < s->l1_size; i++) {
@@ -158,7 +155,7 @@  static int qcow_open(BlockDriverState *bs, const char *filename, int flags)
         len = header.backing_file_size;
         if (len > 1023)
             len = 1023;
-        if (bdrv_pread(s->hd, header.backing_file_offset, bs->backing_file, len) != len)
+        if (bdrv_pread(bs->file, header.backing_file_offset, bs->backing_file, len) != len)
             goto fail;
         bs->backing_file[len] = '\0';
     }
@@ -169,7 +166,7 @@  static int qcow_open(BlockDriverState *bs, const char *filename, int flags)
     qemu_free(s->l2_cache);
     qemu_free(s->cluster_cache);
     qemu_free(s->cluster_data);
-    bdrv_delete(s->hd);
+    bdrv_delete(bs->file);
     return -1;
 }
 
@@ -271,13 +268,13 @@  static uint64_t get_cluster_offset(BlockDriverState *bs,
         if (!allocate)
             return 0;
         /* allocate a new l2 entry */
-        l2_offset = bdrv_getlength(s->hd);
+        l2_offset = bdrv_getlength(bs->file);
         /* round to cluster size */
         l2_offset = (l2_offset + s->cluster_size - 1) & ~(s->cluster_size - 1);
         /* update the L1 entry */
         s->l1_table[l1_index] = l2_offset;
         tmp = cpu_to_be64(l2_offset);
-        if (bdrv_pwrite(s->hd, s->l1_table_offset + l1_index * sizeof(tmp),
+        if (bdrv_pwrite(bs->file, s->l1_table_offset + l1_index * sizeof(tmp),
                         &tmp, sizeof(tmp)) != sizeof(tmp))
             return 0;
         new_l2_table = 1;
@@ -306,11 +303,11 @@  static uint64_t get_cluster_offset(BlockDriverState *bs,
     l2_table = s->l2_cache + (min_index << s->l2_bits);
     if (new_l2_table) {
         memset(l2_table, 0, s->l2_size * sizeof(uint64_t));
-        if (bdrv_pwrite(s->hd, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) !=
+        if (bdrv_pwrite(bs->file, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) !=
             s->l2_size * sizeof(uint64_t))
             return 0;
     } else {
-        if (bdrv_pread(s->hd, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) !=
+        if (bdrv_pread(bs->file, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) !=
             s->l2_size * sizeof(uint64_t))
             return 0;
     }
@@ -329,22 +326,22 @@  static uint64_t get_cluster_offset(BlockDriverState *bs,
             /* if the cluster is already compressed, we must
                decompress it in the case it is not completely
                overwritten */
-            if (decompress_cluster(s, cluster_offset) < 0)
+            if (decompress_cluster(bs, cluster_offset) < 0)
                 return 0;
-            cluster_offset = bdrv_getlength(s->hd);
+            cluster_offset = bdrv_getlength(bs->file);
             cluster_offset = (cluster_offset + s->cluster_size - 1) &
                 ~(s->cluster_size - 1);
             /* write the cluster content */
-            if (bdrv_pwrite(s->hd, cluster_offset, s->cluster_cache, s->cluster_size) !=
+            if (bdrv_pwrite(bs->file, cluster_offset, s->cluster_cache, s->cluster_size) !=
                 s->cluster_size)
                 return -1;
         } else {
-            cluster_offset = bdrv_getlength(s->hd);
+            cluster_offset = bdrv_getlength(bs->file);
             if (allocate == 1) {
                 /* round to cluster size */
                 cluster_offset = (cluster_offset + s->cluster_size - 1) &
                     ~(s->cluster_size - 1);
-                bdrv_truncate(s->hd, cluster_offset + s->cluster_size);
+                bdrv_truncate(bs->file, cluster_offset + s->cluster_size);
                 /* if encrypted, we must initialize the cluster
                    content which won't be written */
                 if (s->crypt_method &&
@@ -358,7 +355,7 @@  static uint64_t get_cluster_offset(BlockDriverState *bs,
                                             s->cluster_data,
                                             s->cluster_data + 512, 1, 1,
                                             &s->aes_encrypt_key);
-                            if (bdrv_pwrite(s->hd, cluster_offset + i * 512,
+                            if (bdrv_pwrite(bs->file, cluster_offset + i * 512,
                                             s->cluster_data, 512) != 512)
                                 return -1;
                         }
@@ -372,7 +369,7 @@  static uint64_t get_cluster_offset(BlockDriverState *bs,
         /* update L2 table */
         tmp = cpu_to_be64(cluster_offset);
         l2_table[l2_index] = tmp;
-        if (bdrv_pwrite(s->hd,
+        if (bdrv_pwrite(bs->file,
                         l2_offset + l2_index * sizeof(tmp), &tmp, sizeof(tmp)) != sizeof(tmp))
             return 0;
     }
@@ -422,8 +419,9 @@  static int decompress_buffer(uint8_t *out_buf, int out_buf_size,
     return 0;
 }
 
-static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset)
+static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset)
 {
+    BDRVQcowState *s = bs->opaque;
     int ret, csize;
     uint64_t coffset;
 
@@ -431,7 +429,7 @@  static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset)
     if (s->cluster_cache_offset != coffset) {
         csize = cluster_offset >> (63 - s->cluster_bits);
         csize &= (s->cluster_size - 1);
-        ret = bdrv_pread(s->hd, coffset, s->cluster_data, csize);
+        ret = bdrv_pread(bs->file, coffset, s->cluster_data, csize);
         if (ret != csize)
             return -1;
         if (decompress_buffer(s->cluster_cache, s->cluster_size,
@@ -468,11 +466,11 @@  static int qcow_read(BlockDriverState *bs, int64_t sector_num,
                 memset(buf, 0, 512 * n);
             }
         } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
-            if (decompress_cluster(s, cluster_offset) < 0)
+            if (decompress_cluster(bs, cluster_offset) < 0)
                 return -1;
             memcpy(buf, s->cluster_cache + index_in_cluster * 512, 512 * n);
         } else {
-            ret = bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512);
+            ret = bdrv_pread(bs->file, cluster_offset + index_in_cluster * 512, buf, n * 512);
             if (ret != n * 512)
                 return -1;
             if (s->crypt_method) {
@@ -601,7 +599,7 @@  static void qcow_aio_read_cb(void *opaque, int ret)
         }
     } else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) {
         /* add AIO support for compressed blocks ? */
-        if (decompress_cluster(s, acb->cluster_offset) < 0)
+        if (decompress_cluster(bs, acb->cluster_offset) < 0)
             goto done;
         memcpy(acb->buf,
                s->cluster_cache + index_in_cluster * 512, 512 * acb->n);
@@ -614,7 +612,7 @@  static void qcow_aio_read_cb(void *opaque, int ret)
         acb->hd_iov.iov_base = (void *)acb->buf;
         acb->hd_iov.iov_len = acb->n * 512;
         qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
-        acb->hd_aiocb = bdrv_aio_readv(s->hd,
+        acb->hd_aiocb = bdrv_aio_readv(bs->file,
                             (acb->cluster_offset >> 9) + index_in_cluster,
                             &acb->hd_qiov, acb->n, qcow_aio_read_cb, acb);
         if (acb->hd_aiocb == NULL)
@@ -699,7 +697,7 @@  static void qcow_aio_write_cb(void *opaque, int ret)
     acb->hd_iov.iov_base = (void *)src_buf;
     acb->hd_iov.iov_len = acb->n * 512;
     qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
-    acb->hd_aiocb = bdrv_aio_writev(s->hd,
+    acb->hd_aiocb = bdrv_aio_writev(bs->file,
                                     (cluster_offset >> 9) + index_in_cluster,
                                     &acb->hd_qiov, acb->n,
                                     qcow_aio_write_cb, acb);
@@ -739,7 +737,7 @@  static void qcow_close(BlockDriverState *bs)
     qemu_free(s->l2_cache);
     qemu_free(s->cluster_cache);
     qemu_free(s->cluster_data);
-    bdrv_delete(s->hd);
+    bdrv_delete(bs->file);
 }
 
 static int qcow_create(const char *filename, QEMUOptionParameter *options)
@@ -839,9 +837,9 @@  static int qcow_make_empty(BlockDriverState *bs)
     int ret;
 
     memset(s->l1_table, 0, l1_length);
-    if (bdrv_pwrite(s->hd, s->l1_table_offset, s->l1_table, l1_length) < 0)
+    if (bdrv_pwrite(bs->file, s->l1_table_offset, s->l1_table, l1_length) < 0)
 	return -1;
-    ret = bdrv_truncate(s->hd, s->l1_table_offset + l1_length);
+    ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length);
     if (ret < 0)
         return ret;
 
@@ -902,7 +900,7 @@  static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num,
         cluster_offset = get_cluster_offset(bs, sector_num << 9, 2,
                                             out_len, 0, 0);
         cluster_offset &= s->cluster_offset_mask;
-        if (bdrv_pwrite(s->hd, cluster_offset, out_buf, out_len) != out_len) {
+        if (bdrv_pwrite(bs->file, cluster_offset, out_buf, out_len) != out_len) {
             qemu_free(out_buf);
             return -1;
         }
@@ -914,16 +912,13 @@  static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num,
 
 static void qcow_flush(BlockDriverState *bs)
 {
-    BDRVQcowState *s = bs->opaque;
-    bdrv_flush(s->hd);
+    bdrv_flush(bs->file);
 }
 
 static BlockDriverAIOCB *qcow_aio_flush(BlockDriverState *bs,
         BlockDriverCompletionFunc *cb, void *opaque)
 {
-    BDRVQcowState *s = bs->opaque;
-
-    return bdrv_aio_flush(s->hd, cb, opaque);
+    return bdrv_aio_flush(bs->file, cb, opaque);
 }
 
 static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index 639e05e..c11680d 100644
--- a/block/qcow2-cluster.c
+++ b/block/qcow2-cluster.c
@@ -54,27 +54,27 @@  int qcow2_grow_l1_table(BlockDriverState *bs, int min_size)
     memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t));
 
     /* write new table (align to cluster) */
-    BLKDBG_EVENT(s->hd, BLKDBG_L1_GROW_ALLOC_TABLE);
+    BLKDBG_EVENT(bs->file, BLKDBG_L1_GROW_ALLOC_TABLE);
     new_l1_table_offset = qcow2_alloc_clusters(bs, new_l1_size2);
     if (new_l1_table_offset < 0) {
         qemu_free(new_l1_table);
         return new_l1_table_offset;
     }
 
-    BLKDBG_EVENT(s->hd, BLKDBG_L1_GROW_WRITE_TABLE);
+    BLKDBG_EVENT(bs->file, BLKDBG_L1_GROW_WRITE_TABLE);
     for(i = 0; i < s->l1_size; i++)
         new_l1_table[i] = cpu_to_be64(new_l1_table[i]);
-    ret = bdrv_pwrite(s->hd, new_l1_table_offset, new_l1_table, new_l1_size2);
+    ret = bdrv_pwrite(bs->file, new_l1_table_offset, new_l1_table, new_l1_size2);
     if (ret != new_l1_size2)
         goto fail;
     for(i = 0; i < s->l1_size; i++)
         new_l1_table[i] = be64_to_cpu(new_l1_table[i]);
 
     /* set new table */
-    BLKDBG_EVENT(s->hd, BLKDBG_L1_GROW_ACTIVATE_TABLE);
+    BLKDBG_EVENT(bs->file, BLKDBG_L1_GROW_ACTIVATE_TABLE);
     cpu_to_be32w((uint32_t*)data, new_l1_size);
     cpu_to_be64w((uint64_t*)(data + 4), new_l1_table_offset);
-    ret = bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_size), data,sizeof(data));
+    ret = bdrv_pwrite(bs->file, offsetof(QCowHeader, l1_size), data,sizeof(data));
     if (ret != sizeof(data)) {
         goto fail;
     }
@@ -174,8 +174,8 @@  static uint64_t *l2_load(BlockDriverState *bs, uint64_t l2_offset)
     min_index = l2_cache_new_entry(bs);
     l2_table = s->l2_cache + (min_index << s->l2_bits);
 
-    BLKDBG_EVENT(s->hd, BLKDBG_L2_LOAD);
-    if (bdrv_pread(s->hd, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) !=
+    BLKDBG_EVENT(bs->file, BLKDBG_L2_LOAD);
+    if (bdrv_pread(bs->file, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) !=
         s->l2_size * sizeof(uint64_t))
         return NULL;
     s->l2_cache_offsets[min_index] = l2_offset;
@@ -189,8 +189,9 @@  static uint64_t *l2_load(BlockDriverState *bs, uint64_t l2_offset)
  * and we really don't want bdrv_pread to perform a read-modify-write)
  */
 #define L1_ENTRIES_PER_SECTOR (512 / 8)
-static int write_l1_entry(BDRVQcowState *s, int l1_index)
+static int write_l1_entry(BlockDriverState *bs, int l1_index)
 {
+    BDRVQcowState *s = bs->opaque;
     uint64_t buf[L1_ENTRIES_PER_SECTOR];
     int l1_start_index;
     int i, ret;
@@ -200,8 +201,8 @@  static int write_l1_entry(BDRVQcowState *s, int l1_index)
         buf[i] = cpu_to_be64(s->l1_table[l1_start_index + i]);
     }
 
-    BLKDBG_EVENT(s->hd, BLKDBG_L1_UPDATE);
-    ret = bdrv_pwrite(s->hd, s->l1_table_offset + 8 * l1_start_index,
+    BLKDBG_EVENT(bs->file, BLKDBG_L1_UPDATE);
+    ret = bdrv_pwrite(bs->file, s->l1_table_offset + 8 * l1_start_index,
         buf, sizeof(buf));
     if (ret < 0) {
         return ret;
@@ -241,7 +242,7 @@  static int l2_allocate(BlockDriverState *bs, int l1_index, uint64_t **table)
     /* update the L1 entry */
 
     s->l1_table[l1_index] = l2_offset | QCOW_OFLAG_COPIED;
-    ret = write_l1_entry(s, l1_index);
+    ret = write_l1_entry(bs, l1_index);
     if (ret < 0) {
         return ret;
     }
@@ -256,16 +257,16 @@  static int l2_allocate(BlockDriverState *bs, int l1_index, uint64_t **table)
         memset(l2_table, 0, s->l2_size * sizeof(uint64_t));
     } else {
         /* if there was an old l2 table, read it from the disk */
-        BLKDBG_EVENT(s->hd, BLKDBG_L2_ALLOC_COW_READ);
-        ret = bdrv_pread(s->hd, old_l2_offset, l2_table,
+        BLKDBG_EVENT(bs->file, BLKDBG_L2_ALLOC_COW_READ);
+        ret = bdrv_pread(bs->file, old_l2_offset, l2_table,
             s->l2_size * sizeof(uint64_t));
         if (ret < 0) {
             return ret;
         }
     }
     /* write the l2 table to the file */
-    BLKDBG_EVENT(s->hd, BLKDBG_L2_ALLOC_WRITE);
-    ret = bdrv_pwrite(s->hd, l2_offset, l2_table,
+    BLKDBG_EVENT(bs->file, BLKDBG_L2_ALLOC_WRITE);
+    ret = bdrv_pwrite(bs->file, l2_offset, l2_table,
         s->l2_size * sizeof(uint64_t));
     if (ret < 0) {
         return ret;
@@ -348,7 +349,7 @@  static int qcow_read(BlockDriverState *bs, int64_t sector_num,
                 /* read from the base image */
                 n1 = qcow2_backing_read1(bs->backing_hd, sector_num, buf, n);
                 if (n1 > 0) {
-                    BLKDBG_EVENT(s->hd, BLKDBG_READ_BACKING);
+                    BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING);
                     ret = bdrv_read(bs->backing_hd, sector_num, buf, n1);
                     if (ret < 0)
                         return -1;
@@ -357,12 +358,12 @@  static int qcow_read(BlockDriverState *bs, int64_t sector_num,
                 memset(buf, 0, 512 * n);
             }
         } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
-            if (qcow2_decompress_cluster(s, cluster_offset) < 0)
+            if (qcow2_decompress_cluster(bs, cluster_offset) < 0)
                 return -1;
             memcpy(buf, s->cluster_cache + index_in_cluster * 512, 512 * n);
         } else {
-            BLKDBG_EVENT(s->hd, BLKDBG_READ);
-            ret = bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512);
+            BLKDBG_EVENT(bs->file, BLKDBG_READ);
+            ret = bdrv_pread(bs->file, cluster_offset + index_in_cluster * 512, buf, n * 512);
             if (ret != n * 512)
                 return -1;
             if (s->crypt_method) {
@@ -386,7 +387,7 @@  static int copy_sectors(BlockDriverState *bs, uint64_t start_sect,
     n = n_end - n_start;
     if (n <= 0)
         return 0;
-    BLKDBG_EVENT(s->hd, BLKDBG_COW_READ);
+    BLKDBG_EVENT(bs->file, BLKDBG_COW_READ);
     ret = qcow_read(bs, start_sect + n_start, s->cluster_data, n);
     if (ret < 0)
         return ret;
@@ -396,8 +397,8 @@  static int copy_sectors(BlockDriverState *bs, uint64_t start_sect,
                         s->cluster_data, n, 1,
                         &s->aes_encrypt_key);
     }
-    BLKDBG_EVENT(s->hd, BLKDBG_COW_WRITE);
-    ret = bdrv_write(s->hd, (cluster_offset >> 9) + n_start,
+    BLKDBG_EVENT(bs->file, BLKDBG_COW_WRITE);
+    ret = bdrv_write(bs->file, (cluster_offset >> 9) + n_start,
                      s->cluster_data, n);
     if (ret < 0)
         return ret;
@@ -610,9 +611,9 @@  uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
 
     /* compressed clusters never have the copied flag */
 
-    BLKDBG_EVENT(s->hd, BLKDBG_L2_UPDATE_COMPRESSED);
+    BLKDBG_EVENT(bs->file, BLKDBG_L2_UPDATE_COMPRESSED);
     l2_table[l2_index] = cpu_to_be64(cluster_offset);
-    if (bdrv_pwrite(s->hd,
+    if (bdrv_pwrite(bs->file,
                     l2_offset + l2_index * sizeof(uint64_t),
                     l2_table + l2_index,
                     sizeof(uint64_t)) != sizeof(uint64_t))
@@ -626,7 +627,7 @@  uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
  * read-modify-write in bdrv_pwrite
  */
 #define L2_ENTRIES_PER_SECTOR (512 / 8)
-static int write_l2_entries(BDRVQcowState *s, uint64_t *l2_table,
+static int write_l2_entries(BlockDriverState *bs, uint64_t *l2_table,
     uint64_t l2_offset, int l2_index, int num)
 {
     int l2_start_index = l2_index & ~(L1_ENTRIES_PER_SECTOR - 1);
@@ -635,8 +636,8 @@  static int write_l2_entries(BDRVQcowState *s, uint64_t *l2_table,
     size_t len = end_offset - start_offset;
     int ret;
 
-    BLKDBG_EVENT(s->hd, BLKDBG_L2_UPDATE);
-    ret = bdrv_pwrite(s->hd, l2_offset + start_offset,
+    BLKDBG_EVENT(bs->file, BLKDBG_L2_UPDATE);
+    ret = bdrv_pwrite(bs->file, l2_offset + start_offset,
         &l2_table[l2_start_index], len);
     if (ret < 0) {
         return ret;
@@ -693,7 +694,7 @@  int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m)
                     (i << s->cluster_bits)) | QCOW_OFLAG_COPIED);
      }
 
-    ret = write_l2_entries(s, l2_table, l2_offset, l2_index, m->nb_clusters);
+    ret = write_l2_entries(bs, l2_table, l2_offset, l2_index, m->nb_clusters);
     if (ret < 0) {
         goto err;
     }
@@ -877,8 +878,9 @@  static int decompress_buffer(uint8_t *out_buf, int out_buf_size,
     return 0;
 }
 
-int qcow2_decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset)
+int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset)
 {
+    BDRVQcowState *s = bs->opaque;
     int ret, csize, nb_csectors, sector_offset;
     uint64_t coffset;
 
@@ -887,8 +889,8 @@  int qcow2_decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset)
         nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1;
         sector_offset = coffset & 511;
         csize = nb_csectors * 512 - sector_offset;
-        BLKDBG_EVENT(s->hd, BLKDBG_READ_COMPRESSED);
-        ret = bdrv_read(s->hd, coffset >> 9, s->cluster_data, nb_csectors);
+        BLKDBG_EVENT(bs->file, BLKDBG_READ_COMPRESSED);
+        ret = bdrv_read(bs->file, coffset >> 9, s->cluster_data, nb_csectors);
         if (ret < 0) {
             return -1;
         }
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index 47c9978..2661493 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -34,16 +34,17 @@  static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs,
 
 static int cache_refcount_updates = 0;
 
-static int write_refcount_block(BDRVQcowState *s)
+static int write_refcount_block(BlockDriverState *bs)
 {
+    BDRVQcowState *s = bs->opaque;
     size_t size = s->cluster_size;
 
     if (s->refcount_block_cache_offset == 0) {
         return 0;
     }
 
-    BLKDBG_EVENT(s->hd, BLKDBG_REFBLOCK_UPDATE);
-    if (bdrv_pwrite(s->hd, s->refcount_block_cache_offset,
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_UPDATE);
+    if (bdrv_pwrite(bs->file, s->refcount_block_cache_offset,
             s->refcount_block_cache, size) != size)
     {
         return -EIO;
@@ -64,8 +65,8 @@  int qcow2_refcount_init(BlockDriverState *bs)
     refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t);
     s->refcount_table = qemu_malloc(refcount_table_size2);
     if (s->refcount_table_size > 0) {
-        BLKDBG_EVENT(s->hd, BLKDBG_REFTABLE_LOAD);
-        ret = bdrv_pread(s->hd, s->refcount_table_offset,
+        BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_LOAD);
+        ret = bdrv_pread(bs->file, s->refcount_table_offset,
                          s->refcount_table, refcount_table_size2);
         if (ret != refcount_table_size2)
             goto fail;
@@ -92,11 +93,11 @@  static int load_refcount_block(BlockDriverState *bs,
     int ret;
 
     if (cache_refcount_updates) {
-        write_refcount_block(s);
+        write_refcount_block(bs);
     }
 
-    BLKDBG_EVENT(s->hd, BLKDBG_REFBLOCK_LOAD);
-    ret = bdrv_pread(s->hd, refcount_block_offset, s->refcount_block_cache,
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_LOAD);
+    ret = bdrv_pread(bs->file, refcount_block_offset, s->refcount_block_cache,
                      s->cluster_size);
     if (ret != s->cluster_size)
         return -EIO;
@@ -167,7 +168,7 @@  static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index)
     unsigned int refcount_table_index;
     int ret;
 
-    BLKDBG_EVENT(s->hd, BLKDBG_REFBLOCK_ALLOC);
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC);
 
     /* Find the refcount block for the given cluster */
     refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
@@ -212,7 +213,7 @@  static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index)
      */
 
     if (cache_refcount_updates) {
-        ret = write_refcount_block(s);
+        ret = write_refcount_block(bs);
         if (ret < 0) {
             return ret;
         }
@@ -244,8 +245,8 @@  static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index)
     }
 
     /* Now the new refcount block needs to be written to disk */
-    BLKDBG_EVENT(s->hd, BLKDBG_REFBLOCK_ALLOC_WRITE);
-    ret = bdrv_pwrite(s->hd, new_block, s->refcount_block_cache,
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE);
+    ret = bdrv_pwrite(bs->file, new_block, s->refcount_block_cache,
         s->cluster_size);
     if (ret < 0) {
         goto fail_block;
@@ -254,8 +255,8 @@  static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index)
     /* If the refcount table is big enough, just hook the block up there */
     if (refcount_table_index < s->refcount_table_size) {
         uint64_t data64 = cpu_to_be64(new_block);
-        BLKDBG_EVENT(s->hd, BLKDBG_REFBLOCK_ALLOC_HOOKUP);
-        ret = bdrv_pwrite(s->hd,
+        BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_HOOKUP);
+        ret = bdrv_pwrite(bs->file,
             s->refcount_table_offset + refcount_table_index * sizeof(uint64_t),
             &data64, sizeof(data64));
         if (ret < 0) {
@@ -277,7 +278,7 @@  static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index)
      * refcount table at once without producing an inconsistent state in
      * between.
      */
-    BLKDBG_EVENT(s->hd, BLKDBG_REFTABLE_GROW);
+    BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_GROW);
 
     /* Calculate the number of refcount blocks needed so far */
     uint64_t refcount_block_clusters = 1 << (s->cluster_bits - REFCOUNT_SHIFT);
@@ -334,8 +335,8 @@  static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index)
     }
 
     /* Write refcount blocks to disk */
-    BLKDBG_EVENT(s->hd, BLKDBG_REFBLOCK_ALLOC_WRITE_BLOCKS);
-    ret = bdrv_pwrite(s->hd, meta_offset, new_blocks,
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_BLOCKS);
+    ret = bdrv_pwrite(bs->file, meta_offset, new_blocks,
         blocks_clusters * s->cluster_size);
     qemu_free(new_blocks);
     if (ret < 0) {
@@ -347,8 +348,8 @@  static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index)
         cpu_to_be64s(&new_table[i]);
     }
 
-    BLKDBG_EVENT(s->hd, BLKDBG_REFBLOCK_ALLOC_WRITE_TABLE);
-    ret = bdrv_pwrite(s->hd, table_offset, new_table,
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_TABLE);
+    ret = bdrv_pwrite(bs->file, table_offset, new_table,
         table_size * sizeof(uint64_t));
     if (ret < 0) {
         goto fail_table;
@@ -362,8 +363,8 @@  static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index)
     uint8_t data[12];
     cpu_to_be64w((uint64_t*)data, table_offset);
     cpu_to_be32w((uint32_t*)(data + 8), table_clusters);
-    BLKDBG_EVENT(s->hd, BLKDBG_REFBLOCK_ALLOC_SWITCH_TABLE);
-    ret = bdrv_pwrite(s->hd, offsetof(QCowHeader, refcount_table_offset),
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_SWITCH_TABLE);
+    ret = bdrv_pwrite(bs->file, offsetof(QCowHeader, refcount_table_offset),
         data, sizeof(data));
     if (ret < 0) {
         goto fail_table;
@@ -398,9 +399,10 @@  fail_block:
 }
 
 #define REFCOUNTS_PER_SECTOR (512 >> REFCOUNT_SHIFT)
-static int write_refcount_block_entries(BDRVQcowState *s,
+static int write_refcount_block_entries(BlockDriverState *bs,
     int64_t refcount_block_offset, int first_index, int last_index)
 {
+    BDRVQcowState *s = bs->opaque;
     size_t size;
 
     if (cache_refcount_updates) {
@@ -412,8 +414,8 @@  static int write_refcount_block_entries(BDRVQcowState *s,
         & ~(REFCOUNTS_PER_SECTOR - 1);
 
     size = (last_index - first_index) << REFCOUNT_SHIFT;
-    BLKDBG_EVENT(s->hd, BLKDBG_REFBLOCK_UPDATE_PART);
-    if (bdrv_pwrite(s->hd,
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_UPDATE_PART);
+    if (bdrv_pwrite(bs->file,
         refcount_block_offset + (first_index << REFCOUNT_SHIFT),
         &s->refcount_block_cache[first_index], size) != size)
     {
@@ -458,7 +460,7 @@  static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs,
         table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
         if ((old_table_index >= 0) && (table_index != old_table_index)) {
 
-            if (write_refcount_block_entries(s, refcount_block_offset,
+            if (write_refcount_block_entries(bs, refcount_block_offset,
                 first_index, last_index) < 0)
             {
                 return -EIO;
@@ -503,7 +505,7 @@  fail:
 
     /* Write last changed block to disk */
     if (refcount_block_offset != 0) {
-        if (write_refcount_block_entries(s, refcount_block_offset,
+        if (write_refcount_block_entries(bs, refcount_block_offset,
             first_index, last_index) < 0)
         {
             return ret < 0 ? ret : -EIO;
@@ -568,11 +570,10 @@  retry:
 
 int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size)
 {
-    BDRVQcowState *s = bs->opaque;
     int64_t offset;
     int ret;
 
-    BLKDBG_EVENT(s->hd, BLKDBG_CLUSTER_ALLOC);
+    BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC);
     offset = alloc_clusters_noref(bs, size);
     ret = update_refcount(bs, offset, size, 1);
     if (ret < 0) {
@@ -589,7 +590,7 @@  int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
     int64_t offset, cluster_offset;
     int free_in_cluster;
 
-    BLKDBG_EVENT(s->hd, BLKDBG_CLUSTER_ALLOC_BYTES);
+    BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC_BYTES);
     assert(size > 0 && size <= s->cluster_size);
     if (s->free_byte_offset == 0) {
         s->free_byte_offset = qcow2_alloc_clusters(bs, s->cluster_size);
@@ -631,10 +632,9 @@  int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
 void qcow2_free_clusters(BlockDriverState *bs,
                           int64_t offset, int64_t size)
 {
-    BDRVQcowState *s = bs->opaque;
     int ret;
 
-    BLKDBG_EVENT(s->hd, BLKDBG_CLUSTER_FREE);
+    BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_FREE);
     ret = update_refcount(bs, offset, size, -1);
     if (ret < 0) {
         fprintf(stderr, "qcow2_free_clusters failed: %s\n", strerror(-ret));
@@ -718,7 +718,7 @@  int qcow2_update_snapshot_refcount(BlockDriverState *bs,
             l1_table = NULL;
         }
         l1_allocated = 1;
-        if (bdrv_pread(s->hd, l1_table_offset,
+        if (bdrv_pread(bs->file, l1_table_offset,
                        l1_table, l1_size2) != l1_size2)
             goto fail;
         for(i = 0;i < l1_size; i++)
@@ -738,7 +738,7 @@  int qcow2_update_snapshot_refcount(BlockDriverState *bs,
             old_l2_offset = l2_offset;
             l2_offset &= ~QCOW_OFLAG_COPIED;
             l2_modified = 0;
-            if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size)
+            if (bdrv_pread(bs->file, l2_offset, l2_table, l2_size) != l2_size)
                 goto fail;
             for(j = 0; j < s->l2_size; j++) {
                 offset = be64_to_cpu(l2_table[j]);
@@ -777,7 +777,7 @@  int qcow2_update_snapshot_refcount(BlockDriverState *bs,
                 }
             }
             if (l2_modified) {
-                if (bdrv_pwrite(s->hd,
+                if (bdrv_pwrite(bs->file,
                                 l2_offset, l2_table, l2_size) != l2_size)
                     goto fail;
             }
@@ -799,7 +799,7 @@  int qcow2_update_snapshot_refcount(BlockDriverState *bs,
     if (l1_modified) {
         for(i = 0; i < l1_size; i++)
             cpu_to_be64s(&l1_table[i]);
-        if (bdrv_pwrite(s->hd, l1_table_offset, l1_table,
+        if (bdrv_pwrite(bs->file, l1_table_offset, l1_table,
                         l1_size2) != l1_size2)
             goto fail;
         for(i = 0; i < l1_size; i++)
@@ -809,14 +809,14 @@  int qcow2_update_snapshot_refcount(BlockDriverState *bs,
         qemu_free(l1_table);
     qemu_free(l2_table);
     cache_refcount_updates = 0;
-    write_refcount_block(s);
+    write_refcount_block(bs);
     return 0;
  fail:
     if (l1_allocated)
         qemu_free(l1_table);
     qemu_free(l2_table);
     cache_refcount_updates = 0;
-    write_refcount_block(s);
+    write_refcount_block(bs);
     return -EIO;
 }
 
@@ -890,7 +890,7 @@  static int check_refcounts_l2(BlockDriverState *bs,
     l2_size = s->l2_size * sizeof(uint64_t);
     l2_table = qemu_malloc(l2_size);
 
-    if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size)
+    if (bdrv_pread(bs->file, l2_offset, l2_table, l2_size) != l2_size)
         goto fail;
 
     /* Do the actual checks */
@@ -982,7 +982,7 @@  static int check_refcounts_l1(BlockDriverState *bs,
         l1_table = NULL;
     } else {
         l1_table = qemu_malloc(l1_size2);
-        if (bdrv_pread(s->hd, l1_table_offset,
+        if (bdrv_pread(bs->file, l1_table_offset,
                        l1_table, l1_size2) != l1_size2)
             goto fail;
         for(i = 0;i < l1_size; i++)
@@ -1051,7 +1051,7 @@  int qcow2_check_refcounts(BlockDriverState *bs)
     uint16_t *refcount_table;
     int ret, errors = 0;
 
-    size = bdrv_getlength(s->hd);
+    size = bdrv_getlength(bs->file);
     nb_clusters = size_to_clusters(s, size);
     refcount_table = qemu_mallocz(nb_clusters * sizeof(uint16_t));
 
diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c
index 8ddaea2..2a21c17 100644
--- a/block/qcow2-snapshot.c
+++ b/block/qcow2-snapshot.c
@@ -79,7 +79,7 @@  int qcow2_read_snapshots(BlockDriverState *bs)
     s->snapshots = qemu_mallocz(s->nb_snapshots * sizeof(QCowSnapshot));
     for(i = 0; i < s->nb_snapshots; i++) {
         offset = align_offset(offset, 8);
-        if (bdrv_pread(s->hd, offset, &h, sizeof(h)) != sizeof(h))
+        if (bdrv_pread(bs->file, offset, &h, sizeof(h)) != sizeof(h))
             goto fail;
         offset += sizeof(h);
         sn = s->snapshots + i;
@@ -97,13 +97,13 @@  int qcow2_read_snapshots(BlockDriverState *bs)
         offset += extra_data_size;
 
         sn->id_str = qemu_malloc(id_str_size + 1);
-        if (bdrv_pread(s->hd, offset, sn->id_str, id_str_size) != id_str_size)
+        if (bdrv_pread(bs->file, offset, sn->id_str, id_str_size) != id_str_size)
             goto fail;
         offset += id_str_size;
         sn->id_str[id_str_size] = '\0';
 
         sn->name = qemu_malloc(name_size + 1);
-        if (bdrv_pread(s->hd, offset, sn->name, name_size) != name_size)
+        if (bdrv_pread(bs->file, offset, sn->name, name_size) != name_size)
             goto fail;
         offset += name_size;
         sn->name[name_size] = '\0';
@@ -158,24 +158,24 @@  static int qcow_write_snapshots(BlockDriverState *bs)
         h.id_str_size = cpu_to_be16(id_str_size);
         h.name_size = cpu_to_be16(name_size);
         offset = align_offset(offset, 8);
-        if (bdrv_pwrite(s->hd, offset, &h, sizeof(h)) != sizeof(h))
+        if (bdrv_pwrite(bs->file, offset, &h, sizeof(h)) != sizeof(h))
             goto fail;
         offset += sizeof(h);
-        if (bdrv_pwrite(s->hd, offset, sn->id_str, id_str_size) != id_str_size)
+        if (bdrv_pwrite(bs->file, offset, sn->id_str, id_str_size) != id_str_size)
             goto fail;
         offset += id_str_size;
-        if (bdrv_pwrite(s->hd, offset, sn->name, name_size) != name_size)
+        if (bdrv_pwrite(bs->file, offset, sn->name, name_size) != name_size)
             goto fail;
         offset += name_size;
     }
 
     /* update the various header fields */
     data64 = cpu_to_be64(snapshots_offset);
-    if (bdrv_pwrite(s->hd, offsetof(QCowHeader, snapshots_offset),
+    if (bdrv_pwrite(bs->file, offsetof(QCowHeader, snapshots_offset),
                     &data64, sizeof(data64)) != sizeof(data64))
         goto fail;
     data32 = cpu_to_be32(s->nb_snapshots);
-    if (bdrv_pwrite(s->hd, offsetof(QCowHeader, nb_snapshots),
+    if (bdrv_pwrite(bs->file, offsetof(QCowHeader, nb_snapshots),
                     &data32, sizeof(data32)) != sizeof(data32))
         goto fail;
 
@@ -284,7 +284,7 @@  int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info)
     for(i = 0; i < s->l1_size; i++) {
         l1_table[i] = cpu_to_be64(s->l1_table[i]);
     }
-    if (bdrv_pwrite(s->hd, sn->l1_table_offset,
+    if (bdrv_pwrite(bs->file, sn->l1_table_offset,
                     l1_table, s->l1_size * sizeof(uint64_t)) !=
         (s->l1_size * sizeof(uint64_t)))
         goto fail;
@@ -332,10 +332,10 @@  int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
     s->l1_size = sn->l1_size;
     l1_size2 = s->l1_size * sizeof(uint64_t);
     /* copy the snapshot l1 table to the current l1 table */
-    if (bdrv_pread(s->hd, sn->l1_table_offset,
+    if (bdrv_pread(bs->file, sn->l1_table_offset,
                    s->l1_table, l1_size2) != l1_size2)
         goto fail;
-    if (bdrv_pwrite(s->hd, s->l1_table_offset,
+    if (bdrv_pwrite(bs->file, s->l1_table_offset,
                     s->l1_table, l1_size2) != l1_size2)
         goto fail;
     for(i = 0;i < s->l1_size; i++) {
diff --git a/block/qcow2.c b/block/qcow2.c
index 11ce8d1..4949d77 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -77,7 +77,6 @@  static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename)
 static int qcow_read_extensions(BlockDriverState *bs, uint64_t start_offset,
                                 uint64_t end_offset)
 {
-    BDRVQcowState *s = bs->opaque;
     QCowExtension ext;
     uint64_t offset;
 
@@ -95,7 +94,7 @@  static int qcow_read_extensions(BlockDriverState *bs, uint64_t start_offset,
         printf("attemting to read extended header in offset %lu\n", offset);
 #endif
 
-        if (bdrv_pread(s->hd, offset, &ext, sizeof(ext)) != sizeof(ext)) {
+        if (bdrv_pread(bs->file, offset, &ext, sizeof(ext)) != sizeof(ext)) {
             fprintf(stderr, "qcow_handle_extension: ERROR: pread fail from offset %llu\n",
                     (unsigned long long)offset);
             return 1;
@@ -117,7 +116,7 @@  static int qcow_read_extensions(BlockDriverState *bs, uint64_t start_offset,
                         ext.len, sizeof(bs->backing_format));
                 return 2;
             }
-            if (bdrv_pread(s->hd, offset , bs->backing_format,
+            if (bdrv_pread(bs->file, offset , bs->backing_format,
                            ext.len) != ext.len)
                 return 3;
             bs->backing_format[ext.len] = '\0';
@@ -138,17 +137,14 @@  static int qcow_read_extensions(BlockDriverState *bs, uint64_t start_offset,
 }
 
 
-static int qcow_open(BlockDriverState *bs, const char *filename, int flags)
+static int qcow_open(BlockDriverState *bs, int flags)
 {
     BDRVQcowState *s = bs->opaque;
-    int len, i, shift, ret;
+    int len, i, shift;
     QCowHeader header;
     uint64_t ext_end;
 
-    ret = bdrv_file_open(&s->hd, filename, flags);
-    if (ret < 0)
-        return ret;
-    if (bdrv_pread(s->hd, 0, &header, sizeof(header)) != sizeof(header))
+    if (bdrv_pread(bs->file, 0, &header, sizeof(header)) != sizeof(header))
         goto fail;
     be32_to_cpus(&header.magic);
     be32_to_cpus(&header.version);
@@ -202,7 +198,7 @@  static int qcow_open(BlockDriverState *bs, const char *filename, int flags)
     if (s->l1_size > 0) {
         s->l1_table = qemu_mallocz(
             align_offset(s->l1_size * sizeof(uint64_t), 512));
-        if (bdrv_pread(s->hd, s->l1_table_offset, s->l1_table, s->l1_size * sizeof(uint64_t)) !=
+        if (bdrv_pread(bs->file, s->l1_table_offset, s->l1_table, s->l1_size * sizeof(uint64_t)) !=
             s->l1_size * sizeof(uint64_t))
             goto fail;
         for(i = 0;i < s->l1_size; i++) {
@@ -235,7 +231,7 @@  static int qcow_open(BlockDriverState *bs, const char *filename, int flags)
         len = header.backing_file_size;
         if (len > 1023)
             len = 1023;
-        if (bdrv_pread(s->hd, header.backing_file_offset, bs->backing_file, len) != len)
+        if (bdrv_pread(bs->file, header.backing_file_offset, bs->backing_file, len) != len)
             goto fail;
         bs->backing_file[len] = '\0';
     }
@@ -254,7 +250,7 @@  static int qcow_open(BlockDriverState *bs, const char *filename, int flags)
     qemu_free(s->l2_cache);
     qemu_free(s->cluster_cache);
     qemu_free(s->cluster_data);
-    bdrv_delete(s->hd);
+    bdrv_delete(bs->file);
     return -1;
 }
 
@@ -429,7 +425,7 @@  static void qcow_aio_read_cb(void *opaque, int ret)
                 acb->hd_iov.iov_base = (void *)acb->buf;
                 acb->hd_iov.iov_len = acb->cur_nr_sectors * 512;
                 qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
-                BLKDBG_EVENT(s->hd, BLKDBG_READ_BACKING_AIO);
+                BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO);
                 acb->hd_aiocb = bdrv_aio_readv(bs->backing_hd, acb->sector_num,
                                     &acb->hd_qiov, acb->cur_nr_sectors,
 				    qcow_aio_read_cb, acb);
@@ -449,7 +445,7 @@  static void qcow_aio_read_cb(void *opaque, int ret)
         }
     } else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) {
         /* add AIO support for compressed blocks ? */
-        if (qcow2_decompress_cluster(s, acb->cluster_offset) < 0)
+        if (qcow2_decompress_cluster(bs, acb->cluster_offset) < 0)
             goto done;
         memcpy(acb->buf, s->cluster_cache + index_in_cluster * 512,
                512 * acb->cur_nr_sectors);
@@ -465,8 +461,8 @@  static void qcow_aio_read_cb(void *opaque, int ret)
         acb->hd_iov.iov_base = (void *)acb->buf;
         acb->hd_iov.iov_len = acb->cur_nr_sectors * 512;
         qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
-        BLKDBG_EVENT(s->hd, BLKDBG_READ_AIO);
-        acb->hd_aiocb = bdrv_aio_readv(s->hd,
+        BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO);
+        acb->hd_aiocb = bdrv_aio_readv(bs->file,
                             (acb->cluster_offset >> 9) + index_in_cluster,
                             &acb->hd_qiov, acb->cur_nr_sectors,
                             qcow_aio_read_cb, acb);
@@ -621,8 +617,8 @@  static void qcow_aio_write_cb(void *opaque, int ret)
     acb->hd_iov.iov_base = (void *)src_buf;
     acb->hd_iov.iov_len = acb->cur_nr_sectors * 512;
     qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
-    BLKDBG_EVENT(s->hd, BLKDBG_WRITE_AIO);
-    acb->hd_aiocb = bdrv_aio_writev(s->hd,
+    BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO);
+    acb->hd_aiocb = bdrv_aio_writev(bs->file,
                                     (acb->cluster_offset >> 9) + index_in_cluster,
                                     &acb->hd_qiov, acb->cur_nr_sectors,
                                     qcow_aio_write_cb, acb);
@@ -669,7 +665,6 @@  static void qcow_close(BlockDriverState *bs)
     qemu_free(s->cluster_cache);
     qemu_free(s->cluster_data);
     qcow2_refcount_close(bs);
-    bdrv_delete(s->hd);
 }
 
 /*
@@ -739,7 +734,7 @@  static int qcow2_update_ext_header(BlockDriverState *bs,
         backing_file_offset = sizeof(QCowHeader) + offset;
     }
 
-    ret = bdrv_pwrite(s->hd, sizeof(QCowHeader), buf, ext_size);
+    ret = bdrv_pwrite(bs->file, sizeof(QCowHeader), buf, ext_size);
     if (ret < 0) {
         goto fail;
     }
@@ -748,13 +743,13 @@  static int qcow2_update_ext_header(BlockDriverState *bs,
     uint64_t be_backing_file_offset = cpu_to_be64(backing_file_offset);
     uint32_t be_backing_file_size = cpu_to_be32(backing_file_len);
 
-    ret = bdrv_pwrite(s->hd, offsetof(QCowHeader, backing_file_offset),
+    ret = bdrv_pwrite(bs->file, offsetof(QCowHeader, backing_file_offset),
         &be_backing_file_offset, sizeof(uint64_t));
     if (ret < 0) {
         goto fail;
     }
 
-    ret = bdrv_pwrite(s->hd, offsetof(QCowHeader, backing_file_size),
+    ret = bdrv_pwrite(bs->file, offsetof(QCowHeader, backing_file_size),
         &be_backing_file_size, sizeof(uint32_t));
     if (ret < 0) {
         goto fail;
@@ -795,7 +790,6 @@  static int get_bits_from_size(size_t size)
 
 static int preallocate(BlockDriverState *bs)
 {
-    BDRVQcowState *s = bs->opaque;
     uint64_t nb_sectors;
     uint64_t offset;
     int num;
@@ -838,7 +832,7 @@  static int preallocate(BlockDriverState *bs)
     if (meta.cluster_offset != 0) {
         uint8_t buf[512];
         memset(buf, 0, 512);
-        bdrv_write(s->hd, (meta.cluster_offset >> 9) + num - 1, buf, 1);
+        bdrv_write(bs->file, (meta.cluster_offset >> 9) + num - 1, buf, 1);
     }
 
     return 0;
@@ -1095,9 +1089,9 @@  static int qcow_make_empty(BlockDriverState *bs)
     int ret;
 
     memset(s->l1_table, 0, l1_length);
-    if (bdrv_pwrite(s->hd, s->l1_table_offset, s->l1_table, l1_length) < 0)
+    if (bdrv_pwrite(bs->file, s->l1_table_offset, s->l1_table, l1_length) < 0)
         return -1;
-    ret = bdrv_truncate(s->hd, s->l1_table_offset + l1_length);
+    ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length);
     if (ret < 0)
         return ret;
 
@@ -1120,9 +1114,9 @@  static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num,
     if (nb_sectors == 0) {
         /* align end of file to a sector boundary to ease reading with
            sector based I/Os */
-        cluster_offset = bdrv_getlength(s->hd);
+        cluster_offset = bdrv_getlength(bs->file);
         cluster_offset = (cluster_offset + 511) & ~511;
-        bdrv_truncate(s->hd, cluster_offset);
+        bdrv_truncate(bs->file, cluster_offset);
         return 0;
     }
 
@@ -1165,8 +1159,8 @@  static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num,
         if (!cluster_offset)
             return -1;
         cluster_offset &= s->cluster_offset_mask;
-        BLKDBG_EVENT(s->hd, BLKDBG_WRITE_COMPRESSED);
-        if (bdrv_pwrite(s->hd, cluster_offset, out_buf, out_len) != out_len) {
+        BLKDBG_EVENT(bs->file, BLKDBG_WRITE_COMPRESSED);
+        if (bdrv_pwrite(bs->file, cluster_offset, out_buf, out_len) != out_len) {
             qemu_free(out_buf);
             return -1;
         }
@@ -1178,16 +1172,13 @@  static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num,
 
 static void qcow_flush(BlockDriverState *bs)
 {
-    BDRVQcowState *s = bs->opaque;
-    bdrv_flush(s->hd);
+    bdrv_flush(bs->file);
 }
 
 static BlockDriverAIOCB *qcow_aio_flush(BlockDriverState *bs,
          BlockDriverCompletionFunc *cb, void *opaque)
 {
-     BDRVQcowState *s = bs->opaque;
-
-     return bdrv_aio_flush(s->hd, cb, opaque);
+    return bdrv_aio_flush(bs->file, cb, opaque);
 }
 
 static int64_t qcow_vm_state_offset(BDRVQcowState *s)
@@ -1216,7 +1207,7 @@  static void dump_refcounts(BlockDriverState *bs)
     int64_t nb_clusters, k, k1, size;
     int refcount;
 
-    size = bdrv_getlength(s->hd);
+    size = bdrv_getlength(bs->file);
     nb_clusters = size_to_clusters(s, size);
     for(k = 0; k < nb_clusters;) {
         k1 = k;
@@ -1236,7 +1227,7 @@  static int qcow_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
     int growable = bs->growable;
     int ret;
 
-    BLKDBG_EVENT(s->hd, BLKDBG_VMSTATE_SAVE);
+    BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_SAVE);
     bs->growable = 1;
     ret = bdrv_pwrite(bs, qcow_vm_state_offset(s) + pos, buf, size);
     bs->growable = growable;
@@ -1251,7 +1242,7 @@  static int qcow_load_vmstate(BlockDriverState *bs, uint8_t *buf,
     int growable = bs->growable;
     int ret;
 
-    BLKDBG_EVENT(s->hd, BLKDBG_VMSTATE_LOAD);
+    BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_LOAD);
     bs->growable = 1;
     ret = bdrv_pread(bs, qcow_vm_state_offset(s) + pos, buf, size);
     bs->growable = growable;
diff --git a/block/qcow2.h b/block/qcow2.h
index de9397a..5bd08db 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -184,7 +184,7 @@  int qcow2_check_refcounts(BlockDriverState *bs);
 /* qcow2-cluster.c functions */
 int qcow2_grow_l1_table(BlockDriverState *bs, int min_size);
 void qcow2_l2_cache_reset(BlockDriverState *bs);
-int qcow2_decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset);
+int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
 void qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
                      uint8_t *out_buf, const uint8_t *in_buf,
                      int nb_sectors, int enc,
diff --git a/block/raw-posix.c b/block/raw-posix.c
index 8f57ab0..598ea19 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -773,7 +773,7 @@  static BlockDriver bdrv_file = {
     .protocol_name = "file",
     .instance_size = sizeof(BDRVRawState),
     .bdrv_probe = NULL, /* no probe for protocols */
-    .bdrv_open = raw_open,
+    .bdrv_file_open = raw_open,
     .bdrv_read = raw_read,
     .bdrv_write = raw_write,
     .bdrv_close = raw_close,
@@ -1030,7 +1030,7 @@  static BlockDriver bdrv_host_device = {
     .protocol_name        = "host_device",
     .instance_size      = sizeof(BDRVRawState),
     .bdrv_probe_device  = hdev_probe_device,
-    .bdrv_open          = hdev_open,
+    .bdrv_file_open     = hdev_open,
     .bdrv_close         = raw_close,
     .bdrv_create        = hdev_create,
     .create_options     = raw_create_options,
@@ -1145,7 +1145,7 @@  static BlockDriver bdrv_host_floppy = {
     .protocol_name      = "host_floppy",
     .instance_size      = sizeof(BDRVRawState),
     .bdrv_probe_device	= floppy_probe_device,
-    .bdrv_open          = floppy_open,
+    .bdrv_file_open     = floppy_open,
     .bdrv_close         = raw_close,
     .bdrv_create        = hdev_create,
     .create_options     = raw_create_options,
@@ -1245,7 +1245,7 @@  static BlockDriver bdrv_host_cdrom = {
     .protocol_name      = "host_cdrom",
     .instance_size      = sizeof(BDRVRawState),
     .bdrv_probe_device	= cdrom_probe_device,
-    .bdrv_open          = cdrom_open,
+    .bdrv_file_open     = cdrom_open,
     .bdrv_close         = raw_close,
     .bdrv_create        = hdev_create,
     .create_options     = raw_create_options,
@@ -1368,7 +1368,7 @@  static BlockDriver bdrv_host_cdrom = {
     .protocol_name      = "host_cdrom",
     .instance_size      = sizeof(BDRVRawState),
     .bdrv_probe_device	= cdrom_probe_device,
-    .bdrv_open          = cdrom_open,
+    .bdrv_file_open     = cdrom_open,
     .bdrv_close         = raw_close,
     .bdrv_create        = hdev_create,
     .create_options     = raw_create_options,
diff --git a/block/raw-win32.c b/block/raw-win32.c
index eadebeb..745bbde 100644
--- a/block/raw-win32.c
+++ b/block/raw-win32.c
@@ -242,7 +242,7 @@  static BlockDriver bdrv_file = {
     .format_name	= "file",
     .protocol_name	= "file",
     .instance_size	= sizeof(BDRVRawState),
-    .bdrv_open		= raw_open,
+    .bdrv_file_open	= raw_open,
     .bdrv_close		= raw_close,
     .bdrv_create	= raw_create,
     .bdrv_flush		= raw_flush,
@@ -399,7 +399,7 @@  static BlockDriver bdrv_host_device = {
     .protocol_name	= "host_device",
     .instance_size	= sizeof(BDRVRawState),
     .bdrv_probe_device	= hdev_probe_device,
-    .bdrv_open		= hdev_open,
+    .bdrv_file_open	= hdev_open,
     .bdrv_close		= raw_close,
     .bdrv_flush		= raw_flush,
 
diff --git a/block/raw.c b/block/raw.c
index 953e285..4406b8c 100644
--- a/block/raw.c
+++ b/block/raw.c
@@ -3,84 +3,61 @@ 
 #include "block_int.h"
 #include "module.h"
 
-typedef struct RAWState {
-    BlockDriverState *hd;
-} RAWState;
-
-static int raw_open(BlockDriverState *bs, const char *filename, int flags)
+static int raw_open(BlockDriverState *bs, int flags)
 {
-    RAWState *s = bs->opaque;
-    int ret;
-
-    ret = bdrv_file_open(&s->hd, filename, flags);
-    if (!ret) {
-        bs->sg = s->hd->sg;
-    }
-
-    return ret;
+    bs->sg = bs->file->sg;
+    return 0;
 }
 
 static int raw_read(BlockDriverState *bs, int64_t sector_num,
                     uint8_t *buf, int nb_sectors)
 {
-    RAWState *s = bs->opaque;
-    return bdrv_read(s->hd, sector_num, buf, nb_sectors);
+    return bdrv_read(bs->file, sector_num, buf, nb_sectors);
 }
 
 static int raw_write(BlockDriverState *bs, int64_t sector_num,
                      const uint8_t *buf, int nb_sectors)
 {
-    RAWState *s = bs->opaque;
-    return bdrv_write(s->hd, sector_num, buf, nb_sectors);
+    return bdrv_write(bs->file, sector_num, buf, nb_sectors);
 }
 
 static BlockDriverAIOCB *raw_aio_readv(BlockDriverState *bs,
     int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
     BlockDriverCompletionFunc *cb, void *opaque)
 {
-    RAWState *s = bs->opaque;
-
-    return bdrv_aio_readv(s->hd, sector_num, qiov, nb_sectors, cb, opaque);
+    return bdrv_aio_readv(bs->file, sector_num, qiov, nb_sectors, cb, opaque);
 }
 
 static BlockDriverAIOCB *raw_aio_writev(BlockDriverState *bs,
     int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
     BlockDriverCompletionFunc *cb, void *opaque)
 {
-    RAWState *s = bs->opaque;
-
-    return bdrv_aio_writev(s->hd, sector_num, qiov, nb_sectors, cb, opaque);
+    return bdrv_aio_writev(bs->file, sector_num, qiov, nb_sectors, cb, opaque);
 }
 
 static void raw_close(BlockDriverState *bs)
 {
-    RAWState *s = bs->opaque;
-    bdrv_delete(s->hd);
 }
 
 static void raw_flush(BlockDriverState *bs)
 {
-    RAWState *s = bs->opaque;
-    bdrv_flush(s->hd);
+    bdrv_flush(bs->file);
 }
 
 static BlockDriverAIOCB *raw_aio_flush(BlockDriverState *bs,
     BlockDriverCompletionFunc *cb, void *opaque)
 {
-    RAWState *s = bs->opaque;
-    return bdrv_aio_flush(s->hd, cb, opaque);
+    return bdrv_aio_flush(bs->file, cb, opaque);
 }
 
 static int64_t raw_getlength(BlockDriverState *bs)
 {
-    RAWState *s = bs->opaque;
-    return bdrv_getlength(s->hd);
+    return bdrv_getlength(bs->file);
 }
 
 static int raw_truncate(BlockDriverState *bs, int64_t offset)
 {
-    RAWState *s = bs->opaque;
-    return bdrv_truncate(s->hd, offset);
+    return bdrv_truncate(bs->file, offset);
 }
 
 static int raw_probe(const uint8_t *buf, int buf_size, const char *filename)
@@ -90,35 +67,30 @@  static int raw_probe(const uint8_t *buf, int buf_size, const char *filename)
 
 static int raw_is_inserted(BlockDriverState *bs)
 {
-    RAWState *s = bs->opaque;
-    return bdrv_is_inserted(s->hd);
+    return bdrv_is_inserted(bs->file);
 }
 
 static int raw_eject(BlockDriverState *bs, int eject_flag)
 {
-    RAWState *s = bs->opaque;
-    return bdrv_eject(s->hd, eject_flag);
+    return bdrv_eject(bs->file, eject_flag);
 }
 
 static int raw_set_locked(BlockDriverState *bs, int locked)
 {
-    RAWState *s = bs->opaque;
-    bdrv_set_locked(s->hd, locked);
+    bdrv_set_locked(bs->file, locked);
     return 0;
 }
 
 static int raw_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
 {
-   RAWState *s = bs->opaque;
-   return bdrv_ioctl(s->hd, req, buf);
+   return bdrv_ioctl(bs->file, req, buf);
 }
 
 static BlockDriverAIOCB *raw_aio_ioctl(BlockDriverState *bs,
         unsigned long int req, void *buf,
         BlockDriverCompletionFunc *cb, void *opaque)
 {
-   RAWState *s = bs->opaque;
-   return bdrv_aio_ioctl(s->hd, req, buf, cb, opaque);
+   return bdrv_aio_ioctl(bs->file, req, buf, cb, opaque);
 }
 
 static int raw_create(const char *filename, QEMUOptionParameter *options)
@@ -138,7 +110,8 @@  static QEMUOptionParameter raw_create_options[] = {
 static BlockDriver bdrv_raw = {
     .format_name        = "raw",
 
-    .instance_size      = sizeof(RAWState),
+    /* It's really 0, but we need to make qemu_malloc() happy */
+    .instance_size      = 1,
 
     .bdrv_open          = raw_open,
     .bdrv_close         = raw_close,
diff --git a/block/vdi.c b/block/vdi.c
index c91961a..8b85339 100644
--- a/block/vdi.c
+++ b/block/vdi.c
@@ -376,21 +376,15 @@  static int vdi_probe(const uint8_t *buf, int buf_size, const char *filename)
     return result;
 }
 
-static int vdi_open(BlockDriverState *bs, const char *filename, int flags)
+static int vdi_open(BlockDriverState *bs, int flags)
 {
     BDRVVdiState *s = bs->opaque;
     VdiHeader header;
     size_t bmap_size;
-    int ret;
 
     logout("\n");
 
-    ret = bdrv_file_open(&s->hd, filename, flags);
-    if (ret < 0) {
-        return ret;
-    }
-
-    if (bdrv_read(s->hd, 0, (uint8_t *)&header, 1) < 0) {
+    if (bdrv_read(bs->file, 0, (uint8_t *)&header, 1) < 0) {
         goto fail;
     }
 
@@ -442,7 +436,7 @@  static int vdi_open(BlockDriverState *bs, const char *filename, int flags)
     bmap_size = header.blocks_in_image * sizeof(uint32_t);
     bmap_size = (bmap_size + SECTOR_SIZE - 1) / SECTOR_SIZE;
     s->bmap = qemu_malloc(bmap_size * SECTOR_SIZE);
-    if (bdrv_read(s->hd, s->bmap_sector, (uint8_t *)s->bmap, bmap_size) < 0) {
+    if (bdrv_read(bs->file, s->bmap_sector, (uint8_t *)s->bmap, bmap_size) < 0) {
         goto fail_free_bmap;
     }
 
@@ -452,7 +446,7 @@  static int vdi_open(BlockDriverState *bs, const char *filename, int flags)
     qemu_free(s->bmap);
 
  fail:
-    bdrv_delete(s->hd);
+    bdrv_delete(bs->file);
     return -1;
 }
 
@@ -607,7 +601,7 @@  static void vdi_aio_read_cb(void *opaque, int ret)
         acb->hd_iov.iov_base = (void *)acb->buf;
         acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE;
         qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
-        acb->hd_aiocb = bdrv_aio_readv(s->hd, offset, &acb->hd_qiov,
+        acb->hd_aiocb = bdrv_aio_readv(bs->file, offset, &acb->hd_qiov,
                                        n_sectors, vdi_aio_read_cb, acb);
         if (acb->hd_aiocb == NULL) {
             goto done;
@@ -670,7 +664,7 @@  static void vdi_aio_write_cb(void *opaque, int ret)
             acb->hd_iov.iov_base = acb->block_buffer;
             acb->hd_iov.iov_len = SECTOR_SIZE;
             qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
-            acb->hd_aiocb = bdrv_aio_writev(s->hd, 0, &acb->hd_qiov, 1,
+            acb->hd_aiocb = bdrv_aio_writev(bs->file, 0, &acb->hd_qiov, 1,
                                             vdi_aio_write_cb, acb);
             if (acb->hd_aiocb == NULL) {
                 goto done;
@@ -699,7 +693,7 @@  static void vdi_aio_write_cb(void *opaque, int ret)
             qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
             logout("will write %u block map sectors starting from entry %u\n",
                    n_sectors, bmap_first);
-            acb->hd_aiocb = bdrv_aio_writev(s->hd, offset, &acb->hd_qiov,
+            acb->hd_aiocb = bdrv_aio_writev(bs->file, offset, &acb->hd_qiov,
                                             n_sectors, vdi_aio_write_cb, acb);
             if (acb->hd_aiocb == NULL) {
                 goto done;
@@ -748,7 +742,7 @@  static void vdi_aio_write_cb(void *opaque, int ret)
         acb->hd_iov.iov_base = (void *)block;
         acb->hd_iov.iov_len = s->block_size;
         qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
-        acb->hd_aiocb = bdrv_aio_writev(s->hd, offset,
+        acb->hd_aiocb = bdrv_aio_writev(bs->file, offset,
                                         &acb->hd_qiov, s->block_sectors,
                                         vdi_aio_write_cb, acb);
         if (acb->hd_aiocb == NULL) {
@@ -761,7 +755,7 @@  static void vdi_aio_write_cb(void *opaque, int ret)
         acb->hd_iov.iov_base = (void *)acb->buf;
         acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE;
         qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
-        acb->hd_aiocb = bdrv_aio_writev(s->hd, offset, &acb->hd_qiov,
+        acb->hd_aiocb = bdrv_aio_writev(bs->file, offset, &acb->hd_qiov,
                                         n_sectors, vdi_aio_write_cb, acb);
         if (acb->hd_aiocb == NULL) {
             goto done;
@@ -891,16 +885,12 @@  static int vdi_create(const char *filename, QEMUOptionParameter *options)
 
 static void vdi_close(BlockDriverState *bs)
 {
-    BDRVVdiState *s = bs->opaque;
-    logout("\n");
-    bdrv_delete(s->hd);
 }
 
 static void vdi_flush(BlockDriverState *bs)
 {
-    BDRVVdiState *s = bs->opaque;
     logout("\n");
-    bdrv_flush(s->hd);
+    bdrv_flush(bs->file);
 }
 
 
diff --git a/block/vmdk.c b/block/vmdk.c
index 6fdea1d..5ef4375 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -914,7 +914,7 @@  static BlockDriver bdrv_vmdk = {
     .format_name	= "vmdk",
     .instance_size	= sizeof(BDRVVmdkState),
     .bdrv_probe		= vmdk_probe,
-    .bdrv_open		= vmdk_open,
+    .bdrv_file_open	= vmdk_open,
     .bdrv_read		= vmdk_read,
     .bdrv_write		= vmdk_write,
     .bdrv_close		= vmdk_close,
diff --git a/block/vpc.c b/block/vpc.c
index 950ad58..1d1ae09 100644
--- a/block/vpc.c
+++ b/block/vpc.c
@@ -150,20 +150,16 @@  static int vpc_probe(const uint8_t *buf, int buf_size, const char *filename)
     return 0;
 }
 
-static int vpc_open(BlockDriverState *bs, const char *filename, int flags)
+static int vpc_open(BlockDriverState *bs, int flags)
 {
     BDRVVPCState *s = bs->opaque;
-    int ret, i;
+    int i;
     struct vhd_footer* footer;
     struct vhd_dyndisk_header* dyndisk_header;
     uint8_t buf[HEADER_SIZE];
     uint32_t checksum;
 
-    ret = bdrv_file_open(&s->hd, filename, flags);
-    if (ret < 0)
-        return ret;
-
-    if (bdrv_pread(s->hd, 0, s->footer_buf, HEADER_SIZE) != HEADER_SIZE)
+    if (bdrv_pread(bs->file, 0, s->footer_buf, HEADER_SIZE) != HEADER_SIZE)
         goto fail;
 
     footer = (struct vhd_footer*) s->footer_buf;
@@ -174,7 +170,7 @@  static int vpc_open(BlockDriverState *bs, const char *filename, int flags)
     footer->checksum = 0;
     if (vpc_checksum(s->footer_buf, HEADER_SIZE) != checksum)
         fprintf(stderr, "block-vpc: The header checksum of '%s' is "
-            "incorrect.\n", filename);
+            "incorrect.\n", bs->filename);
 
     // The visible size of a image in Virtual PC depends on the geometry
     // rather than on the size stored in the footer (the size in the footer
@@ -182,7 +178,7 @@  static int vpc_open(BlockDriverState *bs, const char *filename, int flags)
     bs->total_sectors = (int64_t)
         be16_to_cpu(footer->cyls) * footer->heads * footer->secs_per_cyl;
 
-    if (bdrv_pread(s->hd, be64_to_cpu(footer->data_offset), buf, HEADER_SIZE)
+    if (bdrv_pread(bs->file, be64_to_cpu(footer->data_offset), buf, HEADER_SIZE)
             != HEADER_SIZE)
         goto fail;
 
@@ -199,7 +195,7 @@  static int vpc_open(BlockDriverState *bs, const char *filename, int flags)
     s->pagetable = qemu_malloc(s->max_table_entries * 4);
 
     s->bat_offset = be64_to_cpu(dyndisk_header->table_offset);
-    if (bdrv_pread(s->hd, s->bat_offset, s->pagetable,
+    if (bdrv_pread(bs->file, s->bat_offset, s->pagetable,
             s->max_table_entries * 4) != s->max_table_entries * 4)
 	    goto fail;
 
@@ -228,7 +224,7 @@  static int vpc_open(BlockDriverState *bs, const char *filename, int flags)
 
     return 0;
  fail:
-    bdrv_delete(s->hd);
+    bdrv_delete(bs->file);
     return -1;
 }
 
@@ -266,7 +262,7 @@  static inline int64_t get_sector_offset(BlockDriverState *bs,
 
         s->last_bitmap_offset = bitmap_offset;
         memset(bitmap, 0xff, s->bitmap_size);
-        bdrv_pwrite(s->hd, bitmap_offset, bitmap, s->bitmap_size);
+        bdrv_pwrite(bs->file, bitmap_offset, bitmap, s->bitmap_size);
     }
 
 //    printf("sector: %" PRIx64 ", index: %x, offset: %x, bioff: %" PRIx64 ", bloff: %" PRIx64 "\n",
@@ -316,7 +312,7 @@  static int rewrite_footer(BlockDriverState* bs)
     BDRVVPCState *s = bs->opaque;
     int64_t offset = s->free_data_block_offset;
 
-    ret = bdrv_pwrite(s->hd, offset, s->footer_buf, HEADER_SIZE);
+    ret = bdrv_pwrite(bs->file, offset, s->footer_buf, HEADER_SIZE);
     if (ret < 0)
         return ret;
 
@@ -351,7 +347,7 @@  static int64_t alloc_block(BlockDriverState* bs, int64_t sector_num)
 
     // Initialize the block's bitmap
     memset(bitmap, 0xff, s->bitmap_size);
-    bdrv_pwrite(s->hd, s->free_data_block_offset, bitmap, s->bitmap_size);
+    bdrv_pwrite(bs->file, s->free_data_block_offset, bitmap, s->bitmap_size);
 
     // Write new footer (the old one will be overwritten)
     s->free_data_block_offset += s->block_size + s->bitmap_size;
@@ -362,7 +358,7 @@  static int64_t alloc_block(BlockDriverState* bs, int64_t sector_num)
     // Write BAT entry to disk
     bat_offset = s->bat_offset + (4 * index);
     bat_value = be32_to_cpu(s->pagetable[index]);
-    ret = bdrv_pwrite(s->hd, bat_offset, &bat_value, 4);
+    ret = bdrv_pwrite(bs->file, bat_offset, &bat_value, 4);
     if (ret < 0)
         goto fail;
 
@@ -376,7 +372,6 @@  fail:
 static int vpc_read(BlockDriverState *bs, int64_t sector_num,
                     uint8_t *buf, int nb_sectors)
 {
-    BDRVVPCState *s = bs->opaque;
     int ret;
     int64_t offset;
 
@@ -386,7 +381,7 @@  static int vpc_read(BlockDriverState *bs, int64_t sector_num,
         if (offset == -1) {
             memset(buf, 0, 512);
         } else {
-            ret = bdrv_pread(s->hd, offset, buf, 512);
+            ret = bdrv_pread(bs->file, offset, buf, 512);
             if (ret != 512)
                 return -1;
         }
@@ -401,7 +396,6 @@  static int vpc_read(BlockDriverState *bs, int64_t sector_num,
 static int vpc_write(BlockDriverState *bs, int64_t sector_num,
     const uint8_t *buf, int nb_sectors)
 {
-    BDRVVPCState *s = bs->opaque;
     int64_t offset;
     int ret;
 
@@ -414,7 +408,7 @@  static int vpc_write(BlockDriverState *bs, int64_t sector_num,
                 return -1;
         }
 
-        ret = bdrv_pwrite(s->hd, offset, buf, 512);
+        ret = bdrv_pwrite(bs->file, offset, buf, 512);
         if (ret != 512)
             return -1;
 
@@ -590,7 +584,7 @@  static void vpc_close(BlockDriverState *bs)
 #ifdef CACHE
     qemu_free(s->pageentry_u8);
 #endif
-    bdrv_delete(s->hd);
+    bdrv_delete(bs->file);
 }
 
 static QEMUOptionParameter vpc_create_options[] = {
diff --git a/block/vvfat.c b/block/vvfat.c
index 0701df4..5adbe84 100644
--- a/block/vvfat.c
+++ b/block/vvfat.c
@@ -2827,7 +2827,7 @@  static void vvfat_close(BlockDriverState *bs)
 static BlockDriver bdrv_vvfat = {
     .format_name	= "vvfat",
     .instance_size	= sizeof(BDRVVVFATState),
-    .bdrv_open		= vvfat_open,
+    .bdrv_file_open	= vvfat_open,
     .bdrv_read		= vvfat_read,
     .bdrv_write		= vvfat_write,
     .bdrv_close		= vvfat_close,
diff --git a/block_int.h b/block_int.h
index d4067ff..a3afe63 100644
--- a/block_int.h
+++ b/block_int.h
@@ -51,7 +51,8 @@  struct BlockDriver {
     int instance_size;
     int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename);
     int (*bdrv_probe_device)(const char *filename);
-    int (*bdrv_open)(BlockDriverState *bs, const char *filename, int flags);
+    int (*bdrv_open)(BlockDriverState *bs, int flags);
+    int (*bdrv_file_open)(BlockDriverState *bs, const char *filename, int flags);
     int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num,
                      uint8_t *buf, int nb_sectors);
     int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num,
@@ -155,6 +156,8 @@  struct BlockDriverState {
     int media_changed;
 
     BlockDriverState *backing_hd;
+    BlockDriverState *file;
+
     /* async read/write emulation */
 
     void *sync_aiocb;