block: Implement blk_{pread,pwrite}() using generated_co_wrapper

We need to add include/sysemu/block-backend-io.h to the inputs of the
block-gen.c target defined in block/meson.build.

Signed-off-by: Alberto Faria <afaria@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220705161527.1054072-7-afaria@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>

block/block-backend.c

@@ -1563,29 +1563,6 @@ BlockAIOCB *blk_aio_pwrite_zeroes(BlockBackend *blk, int64_t offset,
                         flags | BDRV_REQ_ZERO_WRITE, cb, opaque);
 }
 
-int blk_pread(BlockBackend *blk, int64_t offset, int64_t bytes, void *buf,
-              BdrvRequestFlags flags)
-{
-    int ret;
-    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
-    IO_OR_GS_CODE();
-
-    blk_inc_in_flight(blk);
-    ret = blk_do_preadv(blk, offset, bytes, &qiov, flags);
-    blk_dec_in_flight(blk);
-
-    return ret;
-}
-
-int blk_pwrite(BlockBackend *blk, int64_t offset, int64_t bytes,
-               const void *buf, BdrvRequestFlags flags)
-{
-    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
-    IO_OR_GS_CODE();
-
-    return blk_pwritev_part(blk, offset, bytes, &qiov, 0, flags);
-}
-
 int64_t blk_getlength(BlockBackend *blk)
 {
     IO_CODE();

block/coroutines.h

@@ -112,10 +112,6 @@ bdrv_common_block_status_above(BlockDriverState *bs,
 int generated_co_wrapper
 nbd_do_establish_connection(BlockDriverState *bs, bool blocking, Error **errp);
 
-int generated_co_wrapper
-blk_do_preadv(BlockBackend *blk, int64_t offset, int64_t bytes,
-              QEMUIOVector *qiov, BdrvRequestFlags flags);
-
 int generated_co_wrapper
 blk_do_pwritev_part(BlockBackend *blk, int64_t offset, int64_t bytes,
                     QEMUIOVector *qiov, size_t qiov_offset,

block/meson.build

@@ -136,6 +136,7 @@ block_gen_c = custom_target('block-gen.c',
                             input: files(
                                       '../include/block/block-io.h',
                                       '../include/block/block-global-state.h',
+                                      '../include/sysemu/block-backend-io.h',
                                       'coroutines.h'
                                       ),
                             command: [wrapper_py, '@OUTPUT@', '@INPUT@'])

include/sysemu/block-backend-io.h

@@ -101,10 +101,12 @@ int coroutine_fn blk_co_copy_range(BlockBackend *blk_in, int64_t off_in,
  * the "I/O or GS" API.
  */
 
-int blk_pread(BlockBackend *blk, int64_t offset, int64_t bytes, void *buf,
-              BdrvRequestFlags flags);
-int blk_pwrite(BlockBackend *blk, int64_t offset, int64_t bytes,
-               const void *buf, BdrvRequestFlags flags);
+int generated_co_wrapper blk_pread(BlockBackend *blk, int64_t offset,
+                                   int64_t bytes, void *buf,
+                                   BdrvRequestFlags flags);
+int generated_co_wrapper blk_pwrite(BlockBackend *blk, int64_t offset,
+                                    int64_t bytes, const void *buf,
+                                    BdrvRequestFlags flags);
 int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset,
                                int64_t bytes, QEMUIOVector *qiov,
                                BdrvRequestFlags flags);