Putting zoned/non-zoned BlockDrivers on top of each other is not
allowed.
Signed-off-by: Sam Li <faithilike...@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefa...@redhat.com>
Reviewed-by: Hannes Reinecke <h...@suse.de>
Reviewed-by: Dmitry Fomichev <dmitry.fomic...@wdc.com>
---
block.c | 19 +++++++++++++++++++
block/file-posix.c | 12 ++++++++++++
block/raw-format.c | 1 +
include/block/block_int-common.h | 5 +++++
4 files changed, 37 insertions(+)
diff --git a/block.c b/block.c
index 0dd604d0f6..4ebf7bbc90 100644
--- a/block.c
+++ b/block.c
@@ -7953,6 +7953,25 @@ void bdrv_add_child(BlockDriverState *parent_bs,
BlockDriverState *child_bs,
return;
}
+ /*
+ * Non-zoned block drivers do not follow zoned storage constraints
+ * (i.e. sequential writes to zones). Refuse mixing zoned and non-zoned
+ * drivers in a graph.
+ */
+ if (!parent_bs->drv->supports_zoned_children &&
+ child_bs->bl.zoned == BLK_Z_HM) {
+ /*
+ * The host-aware model allows zoned storage constraints and random
+ * write. Allow mixing host-aware and non-zoned drivers. Using
+ * host-aware device as a regular device.
+ */
+ error_setg(errp, "Cannot add a %s child to a %s parent",
+ child_bs->bl.zoned == BLK_Z_HM ? "zoned" : "non-zoned",
+ parent_bs->drv->supports_zoned_children ?
+ "support zoned children" : "not support zoned children");
+ return;
+ }
+
if (!QLIST_EMPTY(&child_bs->parents)) {
error_setg(errp, "The node %s already has a parent",
child_bs->node_name);
diff --git a/block/file-posix.c b/block/file-posix.c
index 0c19cfb5cc..5fa80933c9 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -776,6 +776,18 @@ static int raw_open_common(BlockDriverState *bs, QDict
*options,
goto fail;
}
}
+#ifdef CONFIG_BLKZONED
+ /*
+ * The kernel page cache does not reliably work for writes to SWR zones
+ * of zoned block device because it can not guarantee the order of writes.
+ */
+ if ((bs->bl.zoned != BLK_Z_NONE) &&
+ (!(s->open_flags & O_DIRECT))) {
+ error_setg(errp, "The driver supports zoned devices, and it requires "
+ "cache.direct=on, which was not specified.");
+ return -EINVAL; /* No host kernel page cache */
+ }
+#endif
if (S_ISBLK(st.st_mode)) {
#ifdef __linux__
diff --git a/block/raw-format.c b/block/raw-format.c
index 6e1b9394c8..72e23e7b55 100644
--- a/block/raw-format.c
+++ b/block/raw-format.c
@@ -621,6 +621,7 @@ static void raw_child_perm(BlockDriverState *bs, BdrvChild
*c,
BlockDriver bdrv_raw = {
.format_name = "raw",
.instance_size = sizeof(BDRVRawState),
+ .supports_zoned_children = true,
.bdrv_probe = &raw_probe,
.bdrv_reopen_prepare = &raw_reopen_prepare,
.bdrv_reopen_commit = &raw_reopen_commit,
diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h
index a3efb385e0..1bd2aef4d5 100644
--- a/include/block/block_int-common.h
+++ b/include/block/block_int-common.h
@@ -137,6 +137,11 @@ struct BlockDriver {
*/
bool is_format;
+ /*
+ * Set to true if the BlockDriver supports zoned children.
+ */
+ bool supports_zoned_children;
+
/*
* Drivers not implementing bdrv_parse_filename nor bdrv_open should have
* this field set to true, except ones that are defined only by their
--
2.39.2
