'force-share' is one of the basic BlockdevOptions available for all
drivers, but it's silently ignored by bdrv_reopen_prepare/commit(), so
the user cannot change it and doesn't get an error explaining that it
can't be changed.
One example of how this option is being ignored is that on a
read-write image this should produce an error:
(qemu) qemu-io virtio0 "reopen -o force-share=on"
force-share=on can only be used with read-only images
Since there's no reason why we shouldn't allow changing it and the
implementation is simple let's just do it.
Signed-off-by: Alberto Garcia <be...@igalia.com>
---
block.c | 30 ++++++++++++++++++++++++------
include/block/block.h | 1 +
2 files changed, 25 insertions(+), 6 deletions(-)
diff --git a/block.c b/block.c
index 9aed5c19f4..b6e495b716 100644
--- a/block.c
+++ b/block.c
@@ -788,6 +788,18 @@ static BlockdevDetectZeroesOptions
bdrv_parse_detect_zeroes(QemuOpts *opts,
return detect_zeroes;
}
+static bool bdrv_parse_force_share(QemuOpts *opts, int flags, Error **errp)
+{
+ bool value = qemu_opt_get_bool(opts, BDRV_OPT_FORCE_SHARE, false);
+
+ if (value && (flags & BDRV_O_RDWR)) {
+ error_setg(errp, BDRV_OPT_FORCE_SHARE
+ "=on can only be used with read-only images");
+ }
+
+ return value;
+}
+
/**
* Set open flags for a given discard mode
*
@@ -1373,12 +1385,9 @@ static int bdrv_open_common(BlockDriverState *bs,
BlockBackend *file,
drv = bdrv_find_format(driver_name);
assert(drv != NULL);
- bs->force_share = qemu_opt_get_bool(opts, BDRV_OPT_FORCE_SHARE, false);
-
- if (bs->force_share && (bs->open_flags & BDRV_O_RDWR)) {
- error_setg(errp,
- BDRV_OPT_FORCE_SHARE
- "=on can only be used with read-only images");
+ bs->force_share = bdrv_parse_force_share(opts, bs->open_flags, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
ret = -EINVAL;
goto fail_opts;
}
@@ -3201,6 +3210,14 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state,
BlockReopenQueue *queue,
goto error;
}
+ reopen_state->force_share =
+ bdrv_parse_force_share(opts, reopen_state->flags, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ ret = -EINVAL;
+ goto error;
+ }
+
/* node-name and driver must be unchanged. Put them back into the QDict, so
* that they are checked at the end of this function. */
value = qemu_opt_get(opts, "node-name");
@@ -3359,6 +3376,7 @@ void bdrv_reopen_commit(BDRVReopenState *reopen_state)
bs->open_flags = reopen_state->flags;
bs->read_only = !(reopen_state->flags & BDRV_O_RDWR);
bs->detect_zeroes = reopen_state->detect_zeroes;
+ bs->force_share = reopen_state->force_share;
/* Remove child references from bs->options and bs->explicit_options */
QLIST_FOREACH(child, &bs->children, next) {
diff --git a/include/block/block.h b/include/block/block.h
index f71fa5a1c4..a49a027c54 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -185,6 +185,7 @@ typedef struct BDRVReopenState {
BlockDriverState *bs;
int flags;
BlockdevDetectZeroesOptions detect_zeroes;
+ bool force_share;
uint64_t perm, shared_perm;
QDict *options;
QDict *explicit_options;
--
2.11.0
