block: Inline bdrv_co_block_status_from_*()

With bdrv_filter_bs(), we can easily handle this default filter behavior
in bdrv_co_block_status().

blkdebug wants to have an additional assertion, so it keeps its own
implementation, except bdrv_co_block_status_from_file() needs to be
inlined there.

Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>

block/backup-top.c

@@ -175,8 +175,6 @@ BlockDriver bdrv_backup_top_filter = {
     .bdrv_co_pdiscard           = backup_top_co_pdiscard,
     .bdrv_co_flush              = backup_top_co_flush,
 
-    .bdrv_co_block_status       = bdrv_co_block_status_from_backing,
-
     .bdrv_refresh_filename      = backup_top_refresh_filename,
 
     .bdrv_child_perm            = backup_top_child_perm,

block/blkdebug.c

@@ -752,8 +752,11 @@ static int coroutine_fn blkdebug_co_block_status(BlockDriverState *bs,
         return err;
     }
 
-    return bdrv_co_block_status_from_file(bs, want_zero, offset, bytes,
-                                          pnum, map, file);
+    assert(bs->file && bs->file->bs);
+    *pnum = bytes;
+    *map = offset;
+    *file = bs->file->bs;
+    return BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID;
 }
 
 static void blkdebug_close(BlockDriverState *bs)

block/blklogwrites.c

@@ -515,7 +515,6 @@ static BlockDriver bdrv_blk_log_writes = {
     .bdrv_co_pwrite_zeroes  = blk_log_writes_co_pwrite_zeroes,
     .bdrv_co_flush_to_disk  = blk_log_writes_co_flush_to_disk,
     .bdrv_co_pdiscard       = blk_log_writes_co_pdiscard,
-    .bdrv_co_block_status   = bdrv_co_block_status_from_file,
 
     .is_filter              = true,
     .strong_runtime_opts    = blk_log_writes_strong_runtime_opts,

block/commit.c

@@ -238,7 +238,6 @@ static void bdrv_commit_top_child_perm(BlockDriverState *bs, BdrvChild *c,
 static BlockDriver bdrv_commit_top = {
     .format_name                = "commit_top",
     .bdrv_co_preadv             = bdrv_commit_top_preadv,
-    .bdrv_co_block_status       = bdrv_co_block_status_from_backing,
     .bdrv_refresh_filename      = bdrv_commit_top_refresh_filename,
     .bdrv_child_perm            = bdrv_commit_top_child_perm,
 

block/copy-on-read.c

@@ -146,8 +146,6 @@ static BlockDriver bdrv_copy_on_read = {
     .bdrv_eject                         = cor_eject,
     .bdrv_lock_medium                   = cor_lock_medium,
 
-    .bdrv_co_block_status               = bdrv_co_block_status_from_file,
-
     .has_variable_length                = true,
     .is_filter                          = true,
 };

block/filter-compress.c

@@ -146,8 +146,6 @@ static BlockDriver bdrv_compress = {
     .bdrv_eject                         = compress_eject,
     .bdrv_lock_medium                   = compress_lock_medium,
 
-    .bdrv_co_block_status               = bdrv_co_block_status_from_file,
-
     .has_variable_length                = true,
     .is_filter                          = true,
 };

block/io.c

@@ -2255,36 +2255,6 @@ typedef struct BdrvCoBlockStatusData {
     BlockDriverState **file;
 } BdrvCoBlockStatusData;
 
-int coroutine_fn bdrv_co_block_status_from_file(BlockDriverState *bs,
-                                                bool want_zero,
-                                                int64_t offset,
-                                                int64_t bytes,
-                                                int64_t *pnum,
-                                                int64_t *map,
-                                                BlockDriverState **file)
-{
-    assert(bs->file && bs->file->bs);
-    *pnum = bytes;
-    *map = offset;
-    *file = bs->file->bs;
-    return BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID;
-}
-
-int coroutine_fn bdrv_co_block_status_from_backing(BlockDriverState *bs,
-                                                   bool want_zero,
-                                                   int64_t offset,
-                                                   int64_t bytes,
-                                                   int64_t *pnum,
-                                                   int64_t *map,
-                                                   BlockDriverState **file)
-{
-    assert(bs->backing && bs->backing->bs);
-    *pnum = bytes;
-    *map = offset;
-    *file = bs->backing->bs;
-    return BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID;
-}
-
 /*
  * Returns the allocation status of the specified sectors.
  * Drivers not implementing the functionality are assumed to not support
@@ -2325,6 +2295,7 @@ static int coroutine_fn bdrv_co_block_status(BlockDriverState *bs,
     BlockDriverState *local_file = NULL;
     int64_t aligned_offset, aligned_bytes;
     uint32_t align;
+    bool has_filtered_child;
 
     assert(pnum);
     *pnum = 0;
@@ -2350,7 +2321,8 @@ static int coroutine_fn bdrv_co_block_status(BlockDriverState *bs,
 
     /* Must be non-NULL or bdrv_getlength() would have failed */
     assert(bs->drv);
-    if (!bs->drv->bdrv_co_block_status) {
+    has_filtered_child = bdrv_filter_child(bs);
+    if (!bs->drv->bdrv_co_block_status && !has_filtered_child) {
         *pnum = bytes;
         ret = BDRV_BLOCK_DATA | BDRV_BLOCK_ALLOCATED;
         if (offset + bytes == total_size) {
@@ -2371,9 +2343,20 @@ static int coroutine_fn bdrv_co_block_status(BlockDriverState *bs,
     aligned_offset = QEMU_ALIGN_DOWN(offset, align);
     aligned_bytes = ROUND_UP(offset + bytes, align) - aligned_offset;
 
-    ret = bs->drv->bdrv_co_block_status(bs, want_zero, aligned_offset,
-                                        aligned_bytes, pnum, &local_map,
-                                        &local_file);
+    if (bs->drv->bdrv_co_block_status) {
+        ret = bs->drv->bdrv_co_block_status(bs, want_zero, aligned_offset,
+                                            aligned_bytes, pnum, &local_map,
+                                            &local_file);
+    } else {
+        /* Default code for filters */
+
+        local_file = bdrv_filter_bs(bs);
+        assert(local_file);
+
+        *pnum = aligned_bytes;
+        local_map = aligned_offset;
+        ret = BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID;
+    }
     if (ret < 0) {
         *pnum = 0;
         goto out;

block/mirror.c

@@ -1531,7 +1531,6 @@ static BlockDriver bdrv_mirror_top = {
     .bdrv_co_pwrite_zeroes      = bdrv_mirror_top_pwrite_zeroes,
     .bdrv_co_pdiscard           = bdrv_mirror_top_pdiscard,
     .bdrv_co_flush              = bdrv_mirror_top_flush,
-    .bdrv_co_block_status       = bdrv_co_block_status_from_backing,
     .bdrv_refresh_filename      = bdrv_mirror_top_refresh_filename,
     .bdrv_child_perm            = bdrv_mirror_top_child_perm,
 

block/throttle.c

@@ -260,7 +260,6 @@ static BlockDriver bdrv_throttle = {
     .bdrv_reopen_prepare                =   throttle_reopen_prepare,
     .bdrv_reopen_commit                 =   throttle_reopen_commit,
     .bdrv_reopen_abort                  =   throttle_reopen_abort,
-    .bdrv_co_block_status               =   bdrv_co_block_status_from_file,
 
     .bdrv_co_drain_begin                =   throttle_co_drain_begin,
     .bdrv_co_drain_end                  =   throttle_co_drain_end,

include/block/block_int.h

@@ -1303,28 +1303,6 @@ void bdrv_default_perms(BlockDriverState *bs, BdrvChild *c,
                         uint64_t perm, uint64_t shared,
                         uint64_t *nperm, uint64_t *nshared);
 
-/*
- * Default implementation for drivers to pass bdrv_co_block_status() to
- * their file.
- */
-int coroutine_fn bdrv_co_block_status_from_file(BlockDriverState *bs,
-                                                bool want_zero,
-                                                int64_t offset,
-                                                int64_t bytes,
-                                                int64_t *pnum,
-                                                int64_t *map,
-                                                BlockDriverState **file);
-/*
- * Default implementation for drivers to pass bdrv_co_block_status() to
- * their backing file.
- */
-int coroutine_fn bdrv_co_block_status_from_backing(BlockDriverState *bs,
-                                                   bool want_zero,
-                                                   int64_t offset,
-                                                   int64_t bytes,
-                                                   int64_t *pnum,
-                                                   int64_t *map,
-                                                   BlockDriverState **file);
 const char *bdrv_get_parent_name(const BlockDriverState *bs);
 void blk_dev_change_media_cb(BlockBackend *blk, bool load, Error **errp);
 bool blk_dev_has_removable_media(BlockBackend *blk);