diff --git a/block/io.c b/block/io.c
index 0db1146..1fb7afe 100644
--- a/block/io.c
+++ b/block/io.c
@@ -841,9 +841,10 @@ static int coroutine_fn bdrv_driver_pwritev(BlockDriverState *bs,
 
     if (drv->bdrv_co_writev_flags) {
         ret = drv->bdrv_co_writev_flags(bs, sector_num, nb_sectors, qiov,
-                                        flags);
+                                        flags & bs->supported_write_flags);
+        flags &= ~bs->supported_write_flags;
     } else if (drv->bdrv_co_writev) {
-        assert(drv->supported_write_flags == 0);
+        assert(!bs->supported_write_flags);
         ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, qiov);
     } else {
         BlockAIOCB *acb;
@@ -862,9 +863,7 @@ static int coroutine_fn bdrv_driver_pwritev(BlockDriverState *bs,
     }
 
 emulate_flags:
-    if (ret == 0 && (flags & BDRV_REQ_FUA) &&
-        !(drv->supported_write_flags & BDRV_REQ_FUA))
-    {
+    if (ret == 0 && (flags & BDRV_REQ_FUA)) {
         ret = bdrv_co_flush(bs);
     }
 
diff --git a/block/iscsi.c b/block/iscsi.c
index 4f75204..6d5c1f6 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -456,8 +456,11 @@ iscsi_co_writev_flags(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
     struct IscsiTask iTask;
     uint64_t lba;
     uint32_t num_sectors;
-    bool fua;
+    bool fua = flags & BDRV_REQ_FUA;
 
+    if (fua) {
+        assert(iscsilun->dpofua);
+    }
     if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
         return -EINVAL;
     }
@@ -472,7 +475,6 @@ iscsi_co_writev_flags(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
     num_sectors = sector_qemu2lun(nb_sectors, iscsilun);
     iscsi_co_init_iscsitask(iscsilun, &iTask);
 retry:
-    fua = iscsilun->dpofua && (flags & BDRV_REQ_FUA);
     if (iscsilun->use_16_for_rw) {
         iTask.task = iscsi_write16_task(iscsilun->iscsi, iscsilun->lun, lba,
                                         NULL, num_sectors * iscsilun->block_size,
@@ -1548,6 +1550,9 @@ static int iscsi_open(BlockDriverState *bs, QDict *options, int flags,
     task = NULL;
 
     iscsi_modesense_sync(iscsilun);
+    if (iscsilun->dpofua) {
+        bs->supported_write_flags = BDRV_REQ_FUA;
+    }
 
     /* Check the write protect flag of the LUN if we want to write */
     if (iscsilun->type == TYPE_DISK && (flags & BDRV_O_RDWR) &&
@@ -1841,7 +1846,6 @@ static BlockDriver bdrv_iscsi = {
     .bdrv_co_write_zeroes = iscsi_co_write_zeroes,
     .bdrv_co_readv         = iscsi_co_readv,
     .bdrv_co_writev_flags  = iscsi_co_writev_flags,
-    .supported_write_flags = BDRV_REQ_FUA,
     .bdrv_co_flush_to_disk = iscsi_co_flush,
 
 #ifdef __linux__
diff --git a/block/nbd-client.c b/block/nbd-client.c
index 878e879..5fc96e9 100644
--- a/block/nbd-client.c
+++ b/block/nbd-client.c
@@ -414,6 +414,9 @@ int nbd_client_init(BlockDriverState *bs,
         logout("Failed to negotiate with the NBD server\n");
         return ret;
     }
+    if (client->nbdflags & NBD_FLAG_SEND_FUA) {
+        bs->supported_write_flags = BDRV_REQ_FUA;
+    }
 
     qemu_co_mutex_init(&client->send_mutex);
     qemu_co_mutex_init(&client->free_sema);
diff --git a/block/nbd.c b/block/nbd.c
index fccbfef..a4fba91 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -471,7 +471,6 @@ static BlockDriver bdrv_nbd = {
     .bdrv_file_open             = nbd_open,
     .bdrv_co_readv              = nbd_co_readv,
     .bdrv_co_writev_flags       = nbd_co_writev_flags,
-    .supported_write_flags      = BDRV_REQ_FUA,
     .bdrv_close                 = nbd_close,
     .bdrv_co_flush_to_os        = nbd_co_flush,
     .bdrv_co_discard            = nbd_co_discard,
@@ -490,7 +489,6 @@ static BlockDriver bdrv_nbd_tcp = {
     .bdrv_file_open             = nbd_open,
     .bdrv_co_readv              = nbd_co_readv,
     .bdrv_co_writev_flags       = nbd_co_writev_flags,
-    .supported_write_flags      = BDRV_REQ_FUA,
     .bdrv_close                 = nbd_close,
     .bdrv_co_flush_to_os        = nbd_co_flush,
     .bdrv_co_discard            = nbd_co_discard,
@@ -509,7 +507,6 @@ static BlockDriver bdrv_nbd_unix = {
     .bdrv_file_open             = nbd_open,
     .bdrv_co_readv              = nbd_co_readv,
     .bdrv_co_writev_flags       = nbd_co_writev_flags,
-    .supported_write_flags      = BDRV_REQ_FUA,
     .bdrv_close                 = nbd_close,
     .bdrv_co_flush_to_os        = nbd_co_flush,
     .bdrv_co_discard            = nbd_co_discard,
diff --git a/block/raw_bsd.c b/block/raw_bsd.c
index 5e65fb0..1a1618e 100644
--- a/block/raw_bsd.c
+++ b/block/raw_bsd.c
@@ -204,6 +204,7 @@ static int raw_open(BlockDriverState *bs, QDict *options, int flags,
                     Error **errp)
 {
     bs->sg = bs->file->bs->sg;
+    bs->supported_write_flags = BDRV_REQ_FUA;
 
     if (bs->probed && !bdrv_is_read_only(bs)) {
         fprintf(stderr,
@@ -250,7 +251,6 @@ BlockDriver bdrv_raw = {
     .bdrv_create          = &raw_create,
     .bdrv_co_readv        = &raw_co_readv,
     .bdrv_co_writev_flags = &raw_co_writev_flags,
-    .supported_write_flags = BDRV_REQ_FUA,
     .bdrv_co_write_zeroes = &raw_co_write_zeroes,
     .bdrv_co_discard      = &raw_co_discard,
     .bdrv_co_get_block_status = &raw_co_get_block_status,
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 6fbe648..10f4962 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -158,8 +158,6 @@ struct BlockDriver {
     int coroutine_fn (*bdrv_co_pwritev)(BlockDriverState *bs,
         uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags);
 
-    int supported_write_flags;
-
     /*
      * Efficiently zero a region of the disk image.  Typically an image format
      * would use a compact metadata representation to implement this.  This
@@ -445,6 +443,8 @@ struct BlockDriverState {
 
     /* Alignment requirement for offset/length of I/O requests */
     unsigned int request_alignment;
+    /* Flags honored during pwrite (so far: BDRV_REQ_FUA) */
+    unsigned int supported_write_flags;
 
     /* the following member gives a name to every node on the bs graph. */
     char node_name[32];
