block: add zoned BlockDriver check to block layer

Putting zoned/non-zoned BlockDrivers on top of each other is not
allowed.

Signed-off-by: Sam Li <faithilikerun@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20230508045533.175575-6-faithilikerun@gmail.com
Message-id: 20230324090605.28361-6-faithilikerun@gmail.com
[Adjust commit message prefix as suggested by Philippe Mathieu-Daudé
<philmd@linaro.org> and clarify that the check is about zoned
BlockDrivers.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Sam Li 2023-05-08 12:55:30 +08:00 committed by Stefan Hajnoczi
parent 50c4bcd496
commit 774c726ceb
4 changed files with 37 additions and 0 deletions

19
block.c
View File

@ -7982,6 +7982,25 @@ 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);

View File

@ -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__

View File

@ -623,6 +623,7 @@ 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,

View File

@ -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