From 57f9db9a947f4d32bbd56ed9b1e0989f6c306dfb Mon Sep 17 00:00:00 2001 From: Alberto Garcia Date: Thu, 6 Sep 2018 12:37:06 +0300 Subject: block: Forbid trying to change unsupported options during reopen The bdrv_reopen_prepare() function checks all options passed to each BlockDriverState (in the reopen_state->options QDict) and makes all necessary preparations to apply the option changes requested by the user. Options are removed from the QDict as they are processed, so at the end of bdrv_reopen_prepare() only the options that can't be changed are left. Then a loop goes over all remaining options and verifies that the old and new values are identical, returning an error if they're not. The problem is that at the moment there are options that are removed from the QDict although they can't be changed. The consequence of this is any modification to any of those options is silently ignored: (qemu) qemu-io virtio0 "reopen -o discard=on" This happens when all options from bdrv_runtime_opts are removed from the QDict but then only a few of them are processed. Since it's especially important that "node-name" and "driver" are not changed, the code puts them back into the QDict so they are checked at the end of the function. Instead of putting only those two options back into the QDict, this patch puts all unprocessed options using qemu_opts_to_qdict(). update_flags_from_options() also needs to be modified to prevent BDRV_OPT_CACHE_NO_FLUSH, BDRV_OPT_CACHE_DIRECT and BDRV_OPT_READ_ONLY from going back to the QDict. Signed-off-by: Alberto Garcia Reviewed-by: Max Reitz Signed-off-by: Kevin Wolf --- block.c | 22 +++++++--------------- 1 file changed, 7 insertions(+), 15 deletions(-) (limited to 'block.c') diff --git a/block.c b/block.c index ff1aded4b8..e36ae3e8d1 100644 --- a/block.c +++ b/block.c @@ -1094,19 +1094,19 @@ static void update_flags_from_options(int *flags, QemuOpts *opts) *flags &= ~BDRV_O_CACHE_MASK; assert(qemu_opt_find(opts, BDRV_OPT_CACHE_NO_FLUSH)); - if (qemu_opt_get_bool(opts, BDRV_OPT_CACHE_NO_FLUSH, false)) { + if (qemu_opt_get_bool_del(opts, BDRV_OPT_CACHE_NO_FLUSH, false)) { *flags |= BDRV_O_NO_FLUSH; } assert(qemu_opt_find(opts, BDRV_OPT_CACHE_DIRECT)); - if (qemu_opt_get_bool(opts, BDRV_OPT_CACHE_DIRECT, false)) { + if (qemu_opt_get_bool_del(opts, BDRV_OPT_CACHE_DIRECT, false)) { *flags |= BDRV_O_NOCACHE; } *flags &= ~BDRV_O_RDWR; assert(qemu_opt_find(opts, BDRV_OPT_READ_ONLY)); - if (!qemu_opt_get_bool(opts, BDRV_OPT_READ_ONLY, false)) { + if (!qemu_opt_get_bool_del(opts, BDRV_OPT_READ_ONLY, false)) { *flags |= BDRV_O_RDWR; } @@ -3156,7 +3156,6 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue, BlockDriver *drv; QemuOpts *opts; QDict *orig_reopen_opts; - const char *value; bool read_only; assert(reopen_state != NULL); @@ -3179,17 +3178,10 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue, update_flags_from_options(&reopen_state->flags, opts); - /* 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"); - if (value) { - qdict_put_str(reopen_state->options, "node-name", value); - } - - value = qemu_opt_get(opts, "driver"); - if (value) { - qdict_put_str(reopen_state->options, "driver", value); - } + /* All other options (including node-name and driver) must be unchanged. + * Put them back into the QDict, so that they are checked at the end + * of this function. */ + qemu_opts_to_qdict(opts, reopen_state->options); /* If we are to stay read-only, do not allow permission change * to r/w. Attempting to set to r/w may fail if either BDRV_O_ALLOW_RDWR is -- cgit v1.2.3