[PULL,1/1] block/blkio: use FUA flag on write zeroes only if supported

Commit Message

Stefan Hajnoczi Aug. 12, 2024, 3:55 p.m. UTC

From: Stefano Garzarella <[e-mail]>

libblkio supports BLKIO_REQ_FUA with write zeros requests only since
version 1.4.0, so let's inform the block layer that the blkio driver
supports it only in this case. Otherwise we can have runtime errors
as reported in https://issues.redhat.com/browse/RHEL-32878

Fixes: fd66dbd424 ("blkio: add libblkio block driver")
Cc: [e-mail]
Buglink: https://issues.redhat.com/browse/RHEL-32878
Signed-off-by: Stefano Garzarella <[e-mail]>
Reviewed-by: Eric Blake <[e-mail]>
Reviewed-by: Philippe Mathieu-Daudé <[e-mail]>
Message-id: [e-mail]
Signed-off-by: Stefan Hajnoczi <[e-mail]>
---
 meson.build   | 2 ++
 block/blkio.c | 6 ++++--
 2 files changed, 6 insertions(+), 2 deletions(-)

Patch

diff --git a/meson.build b/meson.build
index c2a050b844..81ecd4bae7 100644
--- a/meson.build
+++ b/meson.build
@@ -2305,6 +2305,8 @@  config_host_data.set('CONFIG_BLKIO', blkio.found())
 if blkio.found()
   config_host_data.set('CONFIG_BLKIO_VHOST_VDPA_FD',
                        blkio.version().version_compare('>=1.3.0'))
+  config_host_data.set('CONFIG_BLKIO_WRITE_ZEROS_FUA',
+                       blkio.version().version_compare('>=1.4.0'))
 endif
 config_host_data.set('CONFIG_CURL', curl.found())
 config_host_data.set('CONFIG_CURSES', curses.found())
diff --git a/block/blkio.c b/block/blkio.c
index 3d9a2e764c..e0e765af63 100644
--- a/block/blkio.c
+++ b/block/blkio.c
@@ -899,8 +899,10 @@  static int blkio_open(BlockDriverState *bs, QDict *options, int flags,
     }
 
     bs->supported_write_flags = BDRV_REQ_FUA | BDRV_REQ_REGISTERED_BUF;
-    bs->supported_zero_flags = BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP |
-                               BDRV_REQ_NO_FALLBACK;
+    bs->supported_zero_flags = BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK;
+#ifdef CONFIG_BLKIO_WRITE_ZEROS_FUA
+    bs->supported_zero_flags |= BDRV_REQ_FUA;
+#endif
 
     qemu_mutex_init(&s->blkio_lock);
     qemu_co_mutex_init(&s->bounce_lock);