block: Open the underlying image file in generic code

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>

1 files changed, 11 insertions, 11 deletions

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++) {